Recruiters are divided on the Nursing Councils recent revisions to the registration process for healthcare workers educated outside New Zealand. Photo: Adobe Stock
Heading into winter, Covid-19 is making headlines thanks to new variants and an increase in case numbers.
Virus levels in wastewater were the highest they've been since December, 2022, according to national surveillance data for the week ending 19 May. And close to 40 people a day were being admitted to hospital with the disease.
Earlier this month, we looked at the rise of a subset of variants referred to as "FLiRT". Descended from JN.1, these new lineages accounted for just over 40 percent of all Covid viruses sequenced from waterwater, according to the latest Environmental Science and Research (ESR) data.
Ahead of Budget 2024, let's recap what we know about Covid restrictions, vaccines, tests, and more.
Government vaccine mandates are long gone. They were scrapped in September, 2022.
The remaining Covid mandates were dropped last year, meaning it is no longer a legal requirement to self-isolate after a positive test.
Free rapid antigen tests (RATs) for at-home testing will be available from participating pharmacies and RAT collection sites until 30 June, Health New Zealand Te Whatu Ora announced in January. RNZ has heard from people around the country who said they were already struggling to find tests. RNZ called several pharmacies: Some had stock while others had run out.
Polymerase chain reaction (PCR) tests are used in some situations by health professionals. Results are generally more accurate than for RATs but take two to five days. There has been no indication those will not continue, because they are an important part of infection control in healthcare settings.
At this point, some are asking: Do the tests still work? Yes, experts have told RNZ. PCR tests and RATs work in different ways and the former are more sensitive. But overall, the new subvariants seem to be detected as well as their predecessors with current diagnostics.
Medical masks were free for everyone until the end of February this year. Special P2/N95 masks remain free for people at higher risk of getting very sick until 30 June, 2024. (You can get them when you pick up RATs).
Covid antiviral medicines, that can help reduce the amount of virus in your body so you don't get as sick, are also freely available to people with a range of risk factors relating to age, ethnicity, vaccination status, and underlying health conditions.
Covid vaccination is available and free for everyone aged 5 and over, while additional doses or boosters are available and free for people over the age of 30. (Some younger people can have additional doses, but eligibility criteria apply).
Hopefully, some answers. Right now, the country's long-term Covid strategy is unclear.
It is unclear whether the supply of free RATs and masks will be extended beyond the mid-year deadline. And whether vaccines will remain free for everyone.
Initially, Covid vaccines and treatments were paid for from a separate fund provided by the government. But from 1 July, 2023, the budget for them was added to the combined pharmaceutical budget; a pot of about $1.5 billion.
Now, Covid vaccines and treatments need to be prioritised against all the other medicines, medical devices, vaccines, and related products funded for New Zealanders.
While the Covid vaccines do not necessarily stop someone becoming infected, they remain good protection against severe illness and death from the disease.
The Public Health Communication Centre Aotearoa has also called for government action in response to the threat of long Covid, when the effects of the virus last longer than 12 weeks.
When asked for insight, a spokesperson from Health Minister Shane Reti's office only said: "The government's investment in health will be part of Budget 2024, announced on Thursday."
Te Whatu Ora still recommends taking a test if you have Covid symptoms. And if you test positive, it is recommended you isolate for five days and update My Health Record so you can easily access help and support if needed.
What if someone in your household tests positive? If you have spent at least eight hours with them in the same home, while the person was infectious, you are recommended to stay at home and do a RAT. Even if you test negative, if symptoms persist, stay at home and test again after 24 and 48 hours. Isolate if necessary.
Again, while these things are recommended, there i s no longer a legal requirement to isolate after a positive test.
However, employers should support employees to stay home in line with health guidance, the Ministry of Business, Innovation and Employment said.
Covid remains a notifiable disease. There are no immediate plans to remove it from the schedule - which is updated as needed, the Ministry of Health told RNZ.
The schedule helps with the monitoring of and response to diseases that pose public health risks. Mostly this involves infectious diseases or diseases that, if present in an area, could create a health risk for the wider population.
Note, this does not mean you have to upload your test result. Rather, health practitioners and the people in charge of medical laboratories officially report, or notify, actual and suspected cases of disease.
As the summer and Pride season are upon us, the San Francisco Department of Public Health (DPH) is urging everyone who wants to but particularly men, trans people, and nonbinary people who have sex with men to get the two-dose regimen of the mpox (aka monkeypox) vaccine.
Mpox never really disappeared, though we haven't had a notable outbreak in SF since the summer of 2022. There was a small uptick in cases here late summer, however, which only got scant media coverage. And, like they did at this time last year, DPH has put out a public service announcement to encourage people to get their second, or their first and second doses of the mpox vaccine if they haven't already.
DPH also notes that the Centers for Disease Control is monitoring a new mpox outbreak that's occurring in the Democratic Republic of Congo. That outbreak involves a different strain of mpox known as clade I mpox which appears to cause more severe illness. The outbreak that occurred around the globe in 2022 was clade II mpox, while clade I mpox is associated with a higher rate of fatalities among those infected.
The CDC notes that mpox is endemic in the Congo, and no cases of clade I mpox have been detected outside the country as of now.
"With summer celebrations such as Pride approaching, now is a great time to protect yourself against mpox by getting vaccinated. The mpox vaccine is available through health systems and at clinics, says SF Health Officer Dr. Susan Philip in a statement. Even if you are fully vaccinated, it is still important to remain diligent since no vaccine is 100% effective."
Symptoms of mpox include a rash that looks like pimples or blisters, and anyone experiencing such a rash should talk to their healthcare provider about getting tested. They should also inform any recent sexual partners in order to stave off further spread of the virus.
The New York City health department has been tracking a growing number of mpox cases there, with 42 new cases in the month of April, and 191 recorded so far this year. Chicago has seen 69 cases in the last six months, but only two cases were recorded last month.
San Francisco has only seen nine new cases of mpox since January 1.
Two doses of the mpox vaccine are required for full vaccination, with these doses spread 28 or more days apart.
The health department encourages people to seek vaccination from their regular healthcare provider, but they can also get vaccinated at SF City Clinic, at the SF AIDS Foundation (see more info here), and at the department's Adult Immunization and Travel Clinic by making an appointment.
Previously: Mpox Cases on the Rise Again in SF, Health Department Warns [August 2023]
Two doses of Bavarian Nordics Jynneos vaccine offer almost complete protection against mpox, according to a new report published today in Morbidity and Mortality Weekly Report. Also today, MMWR published an update on clade II mpox cases in the United States, showing cases have been consistent since October 2023, with most cases occurring in unvaccinated people.
In the first study, on Jynneos, the authors say that despite perceptions that now, 2 years after the global mpox outbreak began (primarily among men who have sex with men [MSM]), cases are rising among the previously vaccinated, there is actually evidence that persistent vaccine-derived immunologic response among persons who received the 2-dose vaccine series exists.
In May 2023, a cluster of mpox cases of occurred among vaccinated MSM, leading people to think vaccine efficacy was waning.
"Public perception of an increase in monkeypox virus (MPXV) infections among fully vaccinated persons during 2024 has further fueled concerns about the 2-dose series, the authors said.
The authors examined health records for 32,819 probable or confirmed US mpox cases reported to the Centers for Disease Control and Prevention from May 11, 2022, to May 1, 2024, and found a total of 24,507 (75%) occurred in unvaccinated persons. There were 271 cases (0.8%) among persons who were fully vaccinated.
Of those 271 cases, only 51 (19%) occurred during 2024. Mpox cases among fully vaccinated persons occurred a median of 266 days after receipt of the second vaccine dose, the authors said.
Overall, fully vaccinated persons had a 0.1% infection rate.
The number of breakthrough infections did not comprise a significant proportion of infections, including during 2024.
The number of breakthrough infections did not comprise a significant proportion of infections, including during 2024, the authors said. With only one in four eligible U.S. persons fully vaccinated, clinicians and public health authorities should continue to focus efforts on increasing vaccine coverage.
In another report, researchers show that from October 1, 2023, through April 30, 2024, the United States has averaged 59 cases of mpox each week, mostly among unvaccinated people.
The weekly average is down significantly from a peak of 3,000 cases per week in summer 2022.
Current cases are mostly reported among males (94%), 90% of whom identify as gay or bisexual. The average age of new case-patients is 34 years, and 34% identify as Hispanic, 32% as White, 25% as Black, 3% as Asian, 2% as multiracial, and 4% as another race.
Since October 2023, five US patients with mpox have died, the authors said.
"The current average of 59 reported cases per week represents a fifty-five-fold reduction, compared with the peak of 3,274 cases reported during the week beginning July 31, 2022 (the peak outbreak week); levels have remained stable since October 2023," the authors concluded.
New data from the RECOVERY trial show that women who contracted COVID-19 during pregnancy had a lower risk of developing long COVID, or post-acute sequelae of SARS-CoV-2 infection (PASC), than other women, according to a study in eClinicalMedicine.
The retrospective study from the National Institutes of Health (NIH) Researching COVID to Enhance Recovery (RECOVER) trial included women ages 18 to 49 years with lab-confirmed SARS-CoV-2 infection from March 2020 through June 2022 seen in 19 US health systems.
PASC was defined as symptoms identified 30 to 180 days postSARS-CoV-2 infection. A total of 83,915 women with COVID-19 acquired outside of pregnancy and 5,397 women with COVID-19 acquired during pregnancy were compared and included in the final analysis.
The authors said this was the first study to compare long-COVID outcomes through the lens of pregnancy.
Overall, the authors found that non-pregnant women were older and had more comorbidities than pregnant women with COVID-19, which may have contributed to the findings that non-pregnant women were significantly more at risk for developing long COVID than were pregnant women.
Pregnant women had an incidence of PASC of 25.5% compared to 33.9% non-pregnant women, an adjusted hazard ratio (aHR) of 0.85 (95% confidence interval [CI], 0.80 to 0.91).
The cumulative incidence of PASC in the 180 days following the incident infection date was 30.8 per 100 people among those with COVID acquired during pregnancy compared with 35.8 per 100 people among those with COVID acquired outside of pregnancy, the authors said.
For pregnant women with COVID-19, the average gestational week at infection was 34 weeks, and the average week of delivery was 39 weeks. Hispanic women made up 27.8% of pregnant women with COVID, compared to 14.3% of non-pregnant women with COVID.
SARS-CoV-2 infection acquired during pregnancy compared with acquired outside of pregnancy was associated with a higher incidence of abnormal heartbeat, abdominal pain, and thromboembolism,
"SARS-CoV-2 infection acquired during pregnancy compared with acquired outside of pregnancy was associated with a higher incidence of abnormal heartbeat, abdominal pain, and thromboembolism," the authors wrote. Pregnant women with COVID were also more likely to be hospitalized during the acute phase of infection compared to non-pregnant women.
Non-pregnant women, however, were more likely to experience joint pain, sleep disorders, cognitive problems, difficulty breathing, brain dysfunction, hair loss, acute pharyngitis (throat infection), malnutrition, malaise and fatigue, and chest pain if they developed long COVID.
"The current findings further our understanding of PASC after acquiring SARS-CoV-2 infection in pregnancy to inform patient counseling and direct future research. Further prospective study is necessary to confirm these findings," the authors concluded.
In this section, we investigate the VL stability of matrix A defined in (16) to determine the global stability of the endemic equilibrium (E_{*}). The following definitions and preliminary lemmas are necessary prerequisites for this examination.
30,48,49,50. Consider a square matrix, denoted as M, endowed with the property of symmetry and positive (negative) definiteness. In this context, the matrix M is succinctly expressed as (M>0) or ((M<0)).
30,48,49,50. We write a matrix (A_{ntimes n}>0(A_{ntimes n}<0)) if (A_{ntimes n}) is symmetric positive (negative) definite.
30,48,49,50. If a positive diagonal matrix (H_{ntimes n}) exists, such that (HA+A^{T}H^{T}<0) then a non-singular matrix (A_{ntimes n}) is VL stable.
30,48,49,50. If a positive diagonal matrix (H_{ntimes n}) exists, such that (HA+A^{T}H^{T}<0) ((>0)) then, a non singular matrix (A_{ntimes n}) is diagonal stable.
The (2times 2) VL stable matrix is determined by the following lemma.
30,48,49,50. Let (B=begin{bmatrix} B_{11} &{} B_{12} \ B_{21} &{} B_{22}\ end{bmatrix}) is VL stable if and only if (B_{11}<0), (B_{22}<0), and (det (B)=B_{11}B_{22}-B_{12}B_{21}>0).
30,48,49,50. Consider the nonsingular (A_{ntimes n}=[A_{ij}]), where ((nge 2)), the positive diagonal matrix (C_{ntimes n}=textrm{diag}(C_{1},ldots , C_{n})), and (D=A^{-1}) such that
$$begin{aligned} {left{ begin{array}{ll} A_{nn}>0,\ widetilde{C}widetilde{A}+(widetilde{C}widetilde{A})^{T}>0,\ widetilde{C}widetilde{D}+(widetilde{C}widetilde{D})^{T}>0. end{array}right. } end{aligned}$$
Then, for (H_{n}>0), it ensures that the matrix expression (HA + A^{T}H^{T}) is positive definite.
We employ the same methodology used in51 to obtain the necessary outcomes for globally asymptotically.
If (R_{0}<1), the system (2) is globally asymptotically stable at ({E}_{0}=left( frac{b}{sigma },0,0,0,0,0 right)).
Taking the Lyapunov function corresponding to all dependent classes of the model
$$begin{aligned} L=m_1(S-S^*)+m_2(E-E^*)+m_3(I_S-I_S^*)+m_4(I_A-I_A^*)+m_5(R-R^*). end{aligned}$$
Taking derivative with respect to t yields
$$begin{aligned} L^prime =m_1S^prime +m_2E^prime +m_3I_S^prime +m_4I_A^prime +m_5R^prime . end{aligned}$$
After utilizing the values derived from system (2) and performing requisite calculations, we obtain:
$$begin{aligned} L ^prime =& ,m_{1}b+(m_2-m_1)frac{beta _{1}SP}{1+alpha _1P}+(m_2-m_1) frac{beta _2S(I_A+I_S)}{1+alpha _2(I_A+I_S)}+(m_1-m_2)varphi E+(m_4-m_2) upsilon E+(m_3-m_4)eta upsilon E\&+ (m_5-m_3)gamma _S I_S+(m_5-m_4)gamma _A I_A-m_1mu S-m_2mu E -m_3mu I_S-m_3delta I_S-m_4mu I_A-m_4delta I_A-m_5mu R. end{aligned}$$
Using (m_1=m_2=m_3=m_4=m_5=1) in the above equation gives
$$begin{aligned} L^prime= & , b-mu S-mu E-mu I_S-delta I_S-mu I_A-delta I_A-mu R\= & {} -left(mu N+delta (I_{A}+I_{S})-bright)<0. end{aligned}$$
Thus, the system (2) is globally asymptotically stable at (E_{0}), whenever (R_{0}<1). (square)
We propose the following Lyapunov function in order to prove the global stability at (E_{*}).
$$begin{aligned} L=m_1(S-S^*)^2+m_2(E-E^*)^2+m_3(I_S-I_S^*)^2+m_4(I_A-I_A^*)^2+m_5(R-R^*)^2+m_6(P-P^*)^2. end{aligned}$$
Here, (m_{1}), (m_{2}), (m_{3}), (w_{4}), (m_{5}), and (w_{6}) are non-negative constants. By taking the derivative of L with respect to time along the trajectories of the model (8), one has
$$begin{aligned} L^prime =2m_1(S-S^*)S^prime +2m_2(E-E^*)E^prime +2m_3(I_S-I_S^*)I_S^prime +2m_4(I_A-I_A^*)I_A^prime +2m_5(R-R^*)R^prime +2m_6(P-P^*)P^prime . end{aligned}$$
Here
$$begin{aligned}&2m_1(S-S^*)S^prime \&quad =2m_1(S-S^*)bigg{-frac{beta _{1}SP}{1+alpha _{1}P}-frac{beta _{2}S(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}+frac{beta _{1}S^*P^*}{1+alpha _{1}P^*}+ frac{beta _{2}S^*(I_A^*+I_S^*)}{1+alpha _{2}(I_A^*+I_S^*)}+varphi (R-R^*)-mu (S-S^*)bigg}\&quad =2m_1(S-S^*)bigg{-bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}bigg)S+bigg(frac{beta _{1}P^*}{1+alpha _{1}P^*}+ frac{beta _{2}(I_A^*+I_S^*)}{1+alpha _{2}(I_A^*+I_S^*)}bigg)S^*+varphi (R-R^*)-mu (S-S^*)bigg}\&quad =2m_1(S-S^*)bigg{-textbf{A}S+textbf{B}S^*+varphi (R-R^*)-mu (S-S^*)bigg}\&quad =2m_1(S-S^*)bigg{-textbf{A}S+textbf{A}S^*-textbf{A}S^*+textbf{B}S^*+varphi (R-R^*)-mu (S-S^*)bigg}\&quad =2m_1(S-S^*)bigg{-textbf{A}(S-S^*)-(textbf{A}-textbf{B})S^*+varphi (R-R^*)-mu (S-S^*)bigg}\&quad =2m_1(S-S^*)bigg{-(textbf{A}+mu )(S-S^*)-(textbf{A}-textbf{B})S^*+varphi (E-E^*)bigg}\&quad =2m_1(S-S^*)bigg{-bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}+mu bigg)(S-S^*) -frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}(P-P^*)\&qquad -frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_A-I_A^*) -frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_S-I_S^*)+varphi (R-R^*)bigg}\&quad =2m_1(S-S^*)bigg{-bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}+mu bigg)(S-S^*)+varphi (R-R^*)\&qquad -frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_S-I_S^*)-frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_A-I_A^*)\&qquad -frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}(P-P^*)bigg},\ end{aligned}$$
$$begin{aligned}&2m_2(E-E^*)E^prime \&quad =2m_2(E-E^*)bigg{bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}bigg)S-bigg(frac{beta _{1}P^*}{1+alpha _{1}P^*}+ frac{beta _{2}(I_A^*+I_S^*)}{1+alpha _{2}(I_A^*+I_S^*)}bigg)S^*-(mu +upsilon )(E-E^*)bigg}\&quad =2m_2(E-E^*)bigg{textbf{A}S-textbf{B}S^*-(mu +upsilon )(E-E^*)bigg}\&quad =2m_2(E-E^*)bigg{textbf{A}S-textbf{A}S^*+textbf{A}S^*-textbf{B}S^*-(mu +upsilon )(E-E^*)bigg}\&quad =2m_2(E-E^*)bigg{textbf{A}(S-S^*)+(textbf{A}-textbf{B})S^*-(mu +upsilon )(E-E^*)bigg}\&quad =2m_2(E-E^*)bigg{bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}bigg)(S-S^*)+ frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}(P-P^*)\&qquad +frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_A-I_A^*) +frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_S-I_S^*)-(mu +upsilon )(E-E^*)bigg}\&quad =2m_2(E-E^*)bigg{bigg(frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}bigg)(S-S^*)-(mu +upsilon )(E-E^*)\&qquad +frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_S-I_S^*)+frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}(I_A-I_A^*)\&qquad +frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}(P-P^*)bigg},\&2m_3(I_S-I_S^*)I_S^prime =2m_3(I_S-I_S^*)bigg{eta upsilon (E-E^*)-(mu +delta +gamma _S+tau _{S})(I_S-I_S^*)bigg},\&2m_4(I_A-I_A^*)I_A^prime =2m_4(I_A-I_A^*)bigg{(1-eta )upsilon (E-E^*)-(mu +delta +gamma _A+tau _{A})(I_A-I_A^*)bigg},\&2m_5(R-R^*)R^prime =2m_5(R-R^*)bigg{gamma _A(I_A-I_A^*)+gamma _S(I_S-I_S^*)-(mu +varphi )(R-R^*)bigg}, quad textrm{and}\&2m_6(P-P^*)P^prime =2m_6(P-P^*)bigg{tau _A(I_A-I_A^*)+tau _S(I_S-I_S^*)-mu _P(P-P^*)bigg}. end{aligned}$$
Using these values in (L^prime), which implies that (L^prime =Z(MA+A^{T}M)Z^{T}.)
Here, (Z=[S-S^*, E-E^*, I_S-I_S^*, I_A-I_A^*, R-R^*, P-P^*]), (M={textbf{diag}}(m_1, m_2, m_3, m_4, m_5, m_6)), and
$$begin{aligned} A= & {} left( begin{array}{ccc} -frac{beta _{1}P}{1+alpha _{1}P}-frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}-mu &{} 0 &{} -frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}\ frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)} &{} -(mu +upsilon ) &{} frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}\ 0 &{} eta upsilon &{} -(mu +delta +gamma _S+tau _{S})\ 0 &{} (1-eta )upsilon &{} 0\ 0 &{} 0 &{} gamma _S\ 0 &{} 0 &{} tau _S\ end{array}right. nonumber \{} & {} left. begin{array}{ccc} -frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))} &{} varphi &{} -frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}\ frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))} &{} 0 &{} frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}\ 0 &{} 0 &{} 0\ -(mu +delta +gamma _A+tau _{A}) &{} 0 &{} 0\ gamma _A &{} -(mu +varphi ) &{} 0\ tau _A &{} 0 &{} -mu _P end{array}right) . end{aligned}$$
(16)
It is important to note that matrix (A_{(n-1)times (n-1)}) is derived from matrix A by removing its final row and column. In accordance with the works of Zahedi and Kargar48, Shao and Shateyi49, Masoumnezhad et al.50, Chien and Shateyi30, and Parsaei et al.29, we introduce a series of lemmas and theorems to examine the global stability of the EE at (E_{*}).
In order to make the calculation easier, we present the matrix (16) in more simplified form as given below:
$$begin{aligned} A=left( begin{array}{cccccc} -a &{} 0 &{} -b &{} -b &{} c &{} -d\ e &{} -f &{} b &{} b &{} 0 &{} d\ 0 &{} g &{} -h &{} 0 &{} 0 &{} 0\ 0 &{} i &{} 0 &{} -j &{} 0 &{} 0\ 0 &{} 0 &{} k &{} l &{} -m &{} 0\ 0 &{} 0 &{} n &{} p &{} 0 &{} -q\ end{array}right) . end{aligned}$$
(17)
Here, (a=frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}+mu), (b=frac{beta _{2}S^*}{(1+alpha _{2}(I_A+I_S))(1+alpha _{2}(I_A^*+I_S^*))}), (c=varphi), (d=frac{beta _{1}S^*}{(1+alpha _{1}P)(1+alpha _{1}P^*)}), (e=frac{beta _{1}P}{1+alpha _{1}P}+frac{beta _{2}(I_A+I_S)}{1+alpha _{2}(I_A+I_S)}), (f=(mu +upsilon )), (g=eta upsilon), (h=(mu +delta +gamma _S+tau _{S})), (i=(1-eta )upsilon), (j=(mu +delta +gamma _A+tau _{A})), (k=gamma _S), (l=gamma _A), (m=(mu +varphi )), (n=tau _S), (p=tau _A), and (q=mu _P).
It is important to note that all the parameters a,b,c,d,e,f,g,h,i,j,k,l,m,n,p, and q are positive. Throughout this paper, it is important to note that (a-e) and (-a+e) are always equal to (mu) and (-mu) respectively. Moreover, we conclude that all the diagonal elements (the negative values) of the matrix A are negative, which is a good sign for stability. We need to compute the eigenvalues to make a definitive conclusion for the global stability of (E_{*}). But finding the eigenvalues of the matrix A is quite time consuming. Therefore, we introduce a series of lemmas and theorems given below to examine whether all the eigenvalues of the matrix A have negative real parts or not?.
The matrix (A_{6times 6}) defined in (17) is VL stable.
Obviously (-A_{66}>0). Consider (C=-widetilde{A}) be a (5times 5) matrix that is produced by eliminating the final row and column (-A). Utilizing Lemma 4.2, we can demonstrate the diagonal stability of matrices (C=-widetilde{A}) and (mathbb{C}=-widetilde{A^{-1}}). Let examine the matrix (C=-widetilde{A}) and (mathbb{C}=-widetilde{A^{-1}}), from (17) we obtain
$$begin{aligned} C=left( begin{array}{ccccc} a &{} 0 &{} b &{} b &{} -c\ -e &{} f &{} -b &{} -b &{} 0\ 0 &{} -g &{} h &{} 0 &{} 0\ 0 &{} -i &{} 0 &{} j &{} 0\ 0 &{} 0 &{} -k &{} -l &{} m end{array}right) , quad textrm{and}quad ,mathbb{C}=frac{1}{det (-A)}left( begin{array}{ccccc} mathbf{{c}_{11}} &{} mathbf{c_{12}} &{} mathbf{c_{13}} &{} mathbf{c_{14}} &{} mathbf{c_{15}}\ mathbf{{c}_{21}} &{} mathbf{c_{22}} &{} mathbf{c_{23}} &{} mathbf{c_{24}} &{} mathbf{c_{25}}\ mathbf{{c}_{31}} &{} mathbf{c_{32}} &{} mathbf{c_{33}} &{} mathbf{c_{34}} &{} mathbf{c_{35}}\ mathbf{{c}_{41}} &{} mathbf{c_{42}} &{} mathbf{c_{43}} &{} mathbf{c_{44}} &{} mathbf{c_{45}}\ mathbf{{c}_{51}} &{} mathbf{c_{52}} &{} mathbf{c_{53}} &{} mathbf{c_{54}} &{} mathbf{c_{55}}\ end{array}right) . end{aligned}$$
Here
$$begin{aligned} det (-A)=-d (a - e) m (g j n +h i p) - left(c e (g j k +h i l) + (b (a - e) h i + (b (a - e) g - a f h) j) mright) q<0, end{aligned}$$
and
$$begin{aligned} mathbf{c_{11}}= & {} -mleft(d g j n + d h i p + b h i q + b g j q - f h j qright),\ mathbf{c_{12}}= & {} -d m (g j n + h i p) + left(c (g j k + h i l) - b (h i + g j) mright) q,\ mathbf{c_{13}}= & {} -f j m (d n + b q) + c left(d i (l n - k p) + (f j k + b i (-k + l)) qright),\ mathbf{c_{14}}= & {} -f h m (d p + b q) + c left(d g (-l n + k p) + (b g (k - l) + f h l) qright),\ mathbf{c_{15}}= & {} -c left(d g j n + d h i p + b h i q + b g j q - f h j qright),\ mathbf{c_{21}}= & {} e h j m q, quad mathbf{c_{22}}=a h j m q,\ mathbf{c_{23}}= & {} d (a - e) j m n + j left(c e k + b (a - e) mright) q,\ mathbf{c_{24}}= & {} d (a - e) h m p + h left(c e l + b (a - e) mright) q,\ mathbf{c_{25}}= & {} c e h j q,quad mathbf{c_{31}}=e g j m q,\ mathbf{c_{32}}= & {} a g j m q,\ mathbf{c_{33}}= & {} -a m left(d i p + b i q - f j qright) + e i left(d m p - c l q + b m qright),\ mathbf{c_{34}}= & {} d (a - e) g m p + g left(c e l + b (a - e) mright) q,\ mathbf{c_{35}}= & {} c e g j q,quad mathbf{c_{41}}=e h i m q,quad mathbf{c_{42}}=a h i m q,\ mathbf{c_{43}}= & {} d (a - e) i m n + i left(c e k + b (a - e) mright) q,\ mathbf{c_{44}}= & {} -a m left(d g n + b g q - f h qright) + e g left(d m n - c k q + b m qright),\ mathbf{c_{45}}= & {} c e h i q,\ mathbf{c_{51}}= & {} e left(g j k + h i lright) q,\ mathbf{c_{52}}= & {} a left(g j k + h i lright) q, \ mathbf{c_{53}}= & {} d (a - e) i (l n - k p) + left(b e i (k - l) + a (f j k + b i (-k + l))right) q,\ mathbf{c_{54}}= & {} d (-a + e) g (l n - k p) + left(b e g (-k + l) + a (b g (k - l) + f h l)right) q,\ mathbf{c_{55}}= & {} d (-a + e) (g j n + h i p) + left(b (-a + e) h i + left(-a b g + b e g + a f hright) jright) q. end{aligned}$$
Since
$$begin{aligned} det (-A)=-d (a - e) m (g j n +h i p) - left(c e (g j k +h i l) + left(b (a - e) h i + (b (a - e) g - a f h) jright) mright) q<0, end{aligned}$$
and
$$begin{aligned} mathbf{c_{55}}=d (-a + e) (g j n + h i p) + left(b (-a + e) h i + ((-a + e)b g + a f h) jright) q. end{aligned}$$
Therefore
$$begin{aligned} mathbb{C}_{55}=frac{-left(mu (d g j n + d h i p + b h i q + b g j q) - a f h j qright)}{-mu m (d g j n + d h i p + b h i q + b g j q)-(c e (g j k + h i l) - a f h j m) q}, end{aligned}$$
which implies that
$$begin{aligned} mathbb{C}_{55}=frac{mu left(d g j n + d h i p + b h i q + b g j qright) - a f h j q}{mu m left(d g j n + d h i p + b h i q + b g j qright)+left(c e (g j k + h i l) - a f h j mright) q}>0. end{aligned}$$
Using the information provided in Lemma 4.2, we assert and demonstrate that (C=-widetilde{A}) and (mathbb{C}=-widetilde{A^{-1}}) exhibit diagonal stability, thereby establishing the VL stability of the matrix A. (square)
In accordance with Theorem 4.6, the matrix (C=-widetilde{A}) is affirmed to possess diagonal stability.
As (C_{55}>0), using Lemma 4.2, we must demonstrate the diagonal stability of the reduced matrix (D=widetilde{C}) and its inverse (mathbb{D}=widetilde{C^{-1}}) to complete the proof. Thus the matrix D can be obtained from the matrix C given in Theorem 4.6, we have
$$begin{aligned} D=left( begin{array}{cccc} a &{} 0 &{} b &{} b\ -e &{} f &{} -b &{} -b\ 0 &{} -g &{} h &{} 0\ 0 &{} -i &{} 0 &{} j end{array}right) , quad textrm{and}quad ,,mathbb{D}=frac{1}{det (C)}left( begin{array}{cccc} mathbf{d_{11}} &{} mathbf{d_{12}} &{} mathbf{d_{13}} &{} mathbf{d_{14}}\ mathbf{d_{21}} &{} mathbf{d_{22}} &{} mathbf{d_{23}} &{} mathbf{d_{24}}\ mathbf{d_{31}} &{} mathbf{d_{32}} &{} mathbf{d_{33}} &{} mathbf{d_{34}}\ mathbf{d_{41}} &{} mathbf{d_{42}} &{} mathbf{d_{43}} &{} mathbf{d_{44}} end{array}right) , end{aligned}$$
here
$$begin{aligned} det (C)=-c e (g j k + h i l) + left(b (-a + e) h i + ((-a + e)b g + a f h) jright) m<0, end{aligned}$$
and
$$begin{aligned} mathbf{d_{11}}= & {} -(b h i + b g j - f h j) m,\ mathbf{d_{12}}= & {} c (g j k + h i l) - b (h i + g j) m,\ mathbf{d_{13}}= & {} c f j k - b left(c i (k - l) + f j mright), \ mathbf{d_{14}}= & {} b c g (k - l) + f h (c l - b m),\ mathbf{d_{21}}= & {} e h j m, mathbf{d_{22}}=a h j m,\ mathbf{d_{23}}= & {} j left(c e k + b (a - e) mright),\ mathbf{d_{24}}= & {} h left(c e l + b (a - e) mright),\ mathbf{d_{31}}= & {} e g j m, mathbf{d_{32}}=a g j m,\ mathbf{d_{33}}= & {} -c e i l + left((-a + e)b i + a f jright) m,\ mathbf{d_{34}}= & {} g left(c e l + b (a - e) mright),\ mathbf{d_{41}}= & {} e h i m, mathbf{d_{42}}=a h i m,\ mathbf{d_{43}}= & {} i left(c e k + b (a - e) mright),\ mathbf{d_{44}}= & {} -c e g k + left((-a + e)b g + a f hright) m. end{aligned}$$
Since
$$begin{aligned} det (C)=-c e (g j k + h i l) + left(b (-a + e) h i + left((-a + e) b g + a f hright) jright) m, end{aligned}$$
and
$$begin{aligned} mathbf{d_{44}}=-c e g k + left((-a + e)b g + a f hright) m. end{aligned}$$
Therefore
$$begin{aligned} mathbb{D}_{44}=frac{c e g k +mu b g m - a f h m}{ce(gjk+hil)+bmu (hi+gj)m-afhjm}>0. end{aligned}$$
(square)
The matrix (mathbb{C}=-widetilde{A^{-1}}) defined in Theorem 4.6 is diagonal stable.
Consider the matrix (mathbb{C}) in 4.6, we see that (mathbb{C}_{55}>0), Using Lemma 4.2, we must demonstrate that the modified matrix (E=widetilde{mathbb{C}}) and its inverse (mathbb{E}=widetilde{mathbb{C}^{-1}}) exhibit diagonal stability. This establishes the completion of the proof. Thus the matrix D can be obtained from the matrix (mathbb{C}) given in Theorem 4.6, we have
$$begin{aligned} E=frac{1}{det (-A)}left( begin{array}{cccc} mathbf{{c}_{11}} &{} mathbf{c_{12}} &{} mathbf{c_{13}} &{} mathbf{c_{14}}\ mathbf{{c}_{21}} &{} mathbf{c_{22}} &{} mathbf{c_{23}} &{} mathbf{c_{24}}\ mathbf{{c}_{31}} &{} mathbf{c_{32}} &{} mathbf{c_{33}} &{} mathbf{c_{34}}\ mathbf{{c}_{41}} &{} mathbf{c_{42}} &{} mathbf{c_{43}} &{} mathbf{c_{44}}\ end{array}right) ,,quad textrm{and}quad ,mathbb{E}=frac{1}{det (mathbb{C})}left( begin{array}{cccc} mathbf{{e}_{11}} &{} mathbf{e_{12}} &{} mathbf{e_{13}} &{} mathbf{e_{14}}\ mathbf{{e}_{21}} &{} mathbf{e_{22}} &{} mathbf{e_{23}} &{} mathbf{e_{24}}\ mathbf{{e}_{31}} &{} mathbf{e_{32}} &{} mathbf{e_{33}} &{} mathbf{e_{34}}\ mathbf{{e}_{41}} &{} mathbf{e_{42}} &{} mathbf{e_{43}} &{} mathbf{e_{44}}\ end{array}right) . end{aligned}$$
Here
$$begin{aligned} det (mathbb{C})&=frac{qell ^{4}}{det (-A)}<0, end{aligned}$$
and
$$begin{aligned} mathbf{e_{11}}= & {} -a qell ^{3}, mathbf{e_{12}}=0, mathbf{e_{13}}=-(d n + b q)ell ^{3},\ mathbf{e_{14}}= & {} -(d p + b q)ell ^{3}, mathbf{e_{21}}=e qell ^{3}, mathbf{e_{22}}=-f qell ^{3},\ mathbf{e_{23}}= & {} (d n + b q)ell ^{3}, mathbf{e_{24}}=(d p + b q)ell ^{3}, mathbf{e_{31}}=0,\ mathbf{e_{32}}= & {} g q ell ^{3}, mathbf{e_{33}}=-h qell ^{3}, mathbf{e_{34}}=0, mathbf{e_{41}}=0,\ mathbf{e_{42}}= & {} i qell ^{3}, mathbf{e_{43}}=0, mathbf{e_{44}}=-j qell ^{3}. end{aligned}$$
Here
$$begin{aligned} ell =left[d (a - e) m (g j n + h i p) + left{c e (g j k + h i l) + left(b (a - e) h i + (b (a - e) g - a f h) jright) mright} qright] end{aligned}$$
Since
$$begin{aligned} det (mathbb{C})&=frac{qell ^{4}}{det (-A)}, end{aligned}$$
and
$$begin{aligned} mathbf{e_{44}}=-j q ell ^{3}. end{aligned}$$
Therefore
$$begin{aligned} mathbb{E}_{44}=frac{-j}{det (-A)ell }>0, end{aligned}$$
where (det (-A)<0) and (ell >0). (square)
The matrix D, as described in Lemma 4.3 and denoted by (widetilde{C}), exhibits diagonal stability.
It is clear that (D_{44}>0). By applying Lemma 4.2, our task is to demonstrate the diagonal stability of the reduced matrix (F=widetilde{D}) and its inverse (mathbb{F}=widetilde{D^{-1}}), thereby completing the proof. Thus from Lemma 4.3, we have
$$begin{aligned} F=left( begin{array}{ccc} a &{} 0 &{} b\ -e &{} f &{} -b\ 0 &{} -g &{} h end{array}right) , quad textrm{and}quad ,,mathbb{F}=frac{1}{det ({D})}left( begin{array}{ccc} mathbf{f_{11}} &{} mathbf{f_{12}} &{} mathbf{f_{13}}\ mathbf{f_{21}} &{} mathbf{f_{22}} &{} mathbf{f_{23}}\ mathbf{f_{31}} &{} mathbf{f_{32}} &{} mathbf{f_{33}} end{array}right) . end{aligned}$$
Here
$$begin{aligned} det (D)=b (-a + e) h i + left((-a + e)b g + a f hright) j>0 (textrm{see} textrm{Proposition} 4.1 (iii)), end{aligned}$$
and (mathbf{f_{11}}=f h j - b (h i + g j)>0 (textrm{see} textrm{Proposition} 4.1 (iv))), (mathbf{f_{12}}=-b (h i + g j)), (mathbf{f_{13}}=b f j), (mathbf{f_{21}}=e h j), (mathbf{f_{22}}=a h j), (mathbf{f_{23}}=b (a - e) j), (mathbf{f_{31}}=e g j), (mathbf{f_{32}}=a g j), (mathbf{f_{33}}=(-a + e) b i + a f j>0 (textrm{see} textrm{Proposition} 4.1 (v))).
Since (det (D)>0), and (mathbf{f_{33}}>0), therefore (mathbb{F}_{33}>0). (square)
The matrix (mathbb{D}), as defined in Lemma 4.3 denoted by (widetilde{C^{-1}}), exhibits diagonal stability.
It is obvious that (mathbb{D}_{44}>0), by employing Lemma 4.2, our task is to demonstrate the diagonal stability of a modified matrix (G=widetilde{mathbb{D}}) and its inverse (mathbb{G}=widetilde{mathbb{D}^{-1}}). This verification serves as the completion of the proof. Thus from Lemma 4.3, we have
$$begin{aligned} G=frac{1}{det (C)}left( begin{array}{ccc} mathbf{d_{11}} &{} mathbf{d_{12}} &{} mathbf{d_{13}}\ mathbf{d_{21}} &{} mathbf{d_{22}} &{} mathbf{d_{23}}\ mathbf{d_{31}} &{} mathbf{d_{32}} &{} mathbf{d_{33}} end{array}right) , quad textrm{and}quad ,mathbb{G}=frac{1}{det (mathbb{D})}left( begin{array}{ccc} mathbf{g_{11}} &{} mathbf{g_{12}} &{} mathbf{g_{13}}\ mathbf{g_{21}} &{} mathbf{g_{22}} &{} mathbf{g_{23}}\ mathbf{g_{31}} &{} mathbf{g_{32}} &{} mathbf{g_{33}} end{array}right) . end{aligned}$$
Here
$$begin{aligned} det (mathbb{D})&=frac{-mell _{1}^{3}}{det (C)}>0, end{aligned}$$
and
$$begin{aligned} mathbf{g_{11}}= & a mell _{1}^{2}, mathbf{g_{12}}=0, mathbf{g_{13}}=-(c k - b m)ell _{1}^{2}, mathbf{g_{21}}=-e mell _{1}^{2}, mathbf{g_{22}}=f mell _{1}^{2}, ,mathbf{g_{23}}= & {} -b mell _{1}^{2}, mathbf{g_{31}}=0, mathbf{g_{32}}=-g mell _{1}^{2}, mathbf{g_{33}}=h mell _{1}^{2}. end{aligned}$$
Here
$$begin{aligned} ell _{1}=left[c e (g j k + h i l) + left{b (a - e) h i + left(b (a - e) g - a f hright) jright} mright] end{aligned}$$
Thursday, May 30, 2024 12:00 pm 1:00 pm EDT; 11:00 am 12:00 pm CDT; 10:00 am 11:00 am MDT; 9:00 am 10:00 am PDT Register
Laura Malone, MD, PhD
Dr. Laura Malone is the director of the Pediatric Post-COVID-19 Rehabilitation Clinicat Kennedy Krieger Institute.She is alsoa physician scientist in Kennedy Kriegers Center for Movement Studies and an assistant professor of Neurology and Physical Medicine and Rehabilitation at the Johns Hopkins University School of Medicine.
Dr. Malone has a PhD in Biomedical Engineering from Johns Hopkins University and her medical degree from the University of North Carolina. She completed her pediatric neurology residency at Johns Hopkins School of Medicine. Dr. Malones clinical practice focuses on the neurological care of children with perinatal stroke, other brain injuries, and long COVID. Her research focuses on understanding complex pediatric disorders and on improving outcomes using mechanistic neurorehabilitation approaches. Regarding COVID-19, Dr. Malone investigates clinical phenotypes of children with persistent symptoms after COVID-19infection and investigates factors and mechanisms that promote good recovery.
Objectives: At the end of this session, the learner will:
Audience: This webinar is intended for all interested members of the rehabilitation team.
Level: Intermediate
Certificate of Attendance: Certificates of attendance are available for all attendees. No CEs are provided for this course.
Complimentary webinars are a benefit of membership in IPRC/RCPA. Registration fee for non-members is $179. Not a member yet?Consider joining today.
Two posters presented at the American Thoracic Society (ATS) 2024 International Conference found that asthma can be diagnosed after COVID-19 like other respiratory viral infections, and that the pandemic exerted a substantial influence on health care utilization for serious asthma outcomes.
Man holding paper model of lungs | Elena - stock.adobe.com
The first poster was based on a retrospective study that analyzed medical records of patients with respiratory symptoms between January 2022 and March 2023, to compare the clinical features and final diagnoses of these patients.1
The study categorized patients as those with recent COVID-19 and those without, assessing clinical features, final diagnoses, and pulmonary function tests. A total of 3,168 patients were included in the study, in which 842 (26.58%) had recent COVID-19 and 2,326 (73.42%) did not.
Patients in the COVID-19 group were more often female (61.6%) and had a significantly lower mean (SD) age (53.45 [17.12] years vs 60 [16.95] years; P < .001) than patients in the nonCOVID-19 group. Additionally, 632 (19.95%) patients were clinically diagnosed with asthma, with 150 (17.8%) in the COVID-19 group and 482 (20.7%) in the non-COVID-19 group, showing no statistical significance (P = .07).
Furthermore, the researchers found no significant difference in forced expiratory volume per 1 second (FEV1) based on COVID-19 status among patients with asthma, while subacute cough was significantly more prevalent in the COVID-19 group (45.7% vs 1.7%; P < .001).
Therefore, the researchers believe that asthma can be diagnosed after COVID-19 in a similar manner to other respiratory viral infections, and that the incidence of asthma diagnosis post-COVID-19 did not significantly differ from patients without a history of COVID-19 infection.
The second poster aimed to examine the impact of the COVID-19 pandemic on health care utilization for pediatric patients with asthma.2
The study included electronic health record (EHR) data encompassing more than 13,000 patients, more than 32,000 records, more than 8700 emergency visits, and more than 4000 hospitalizations for asthma. From this data, the researchers identified 2347 individuals with an index visit1165 pre-pandemic, 289 during the pandemic, and 893 post-pandemic. The mean age of patients was 6.4 (4.4) years, and 40.4% were female. Additionally, 50.8% of patients were White, 41.5% were Black, and 7.7% identified as other race(s).
Times to the next emergency visit were much shorter during the pandemic (253 days) and post-pandemic (101 days) compared with the pre-pandemic (276.5 days), as well as median times to next hospitalization, with 338.5 days during the pandemic, 120 days post-pandemic, and 437 days pre-pandemic, respectively.
Additionally, Black patients had faster median emergency visit returns than White patients both before and during the pandemic but had longer median times post-pandemic. The researchers noted that the effect of the pandemic on emergency visits and hospitalizations tended to be different among groups. Furthermore, the time-to-emergency visit was more pronounced in White patients compared with Black patients (P < .0001).
Therefore, the researchers believe the findings suggest the COVID-19 pandemic had substantial influence on health care utilization for severe asthma outcomes in children, and that these effects have been endured for an extended period.
References
1. Hur G, Chang S, Sim J, et al. Clinical presentation and diagnosis of respiratory symptoms during the COVID-19 pandemic. Abstract presented at: American Thoracic Society International Conference; May 17-22, 2024; San Diego, CA. Accessed May 28, 2024. https://www.abstractsonline.com/pp8/#!/11007/presentation/9405
2. Forno E, Bo N, Liu J, et al. EHR-based survival analysis to examine the impact of the COVID-19 pandemic on severe asthma outcomes in pediatrics. Abstract presented at: American Thoracic Society International Conference; May 17-22, 2024; San Diego, CA. Accessed May 28, 2024. https://www.abstractsonline.com/pp8/#!/11007/presentation/4513
The emergence of COVID-19 and its slow integration into our daily lives has impacted everybody. But that impact hasnt been the same across the board. One reason? The physical experience of being sick with COVID-19 can vary wildly from person to person. Contracting COVID-19 is deadly for some, while others dont get so much as a sniffle. How exactly is that possible?
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Were learning more about COVID-19 every day. And theres so much information out there that it can be hard to keep up. We asked infectious disease specialist Donald Dumford, MD, to bring us up to date on asymptomatic COVID-19. He details the ongoing research on the topic and explains how we can use what we know to navigate our new normal in a smart, safe way.
Simply put, the word asymptomatic means being sick without having symptoms. No fever, no cough, no body aches, no fatigue. Nothing. Your bodys actively battling a disease and in some cases spreading it without you even realizing youre unwell.
Its called being an asymptomatic carrier. Asymptomatic carriage isnt something that happens with all diseases, but it does happen with COVID-19. And it happens quite a bit. Dr. Dumford says its one of the reasons the virus proved impossible to contain and why it transitioned from an isolated outbreak to a global pandemic so quickly.
Dr. Dumford notes that its common to confuse asymptomatic COVID-19 with pre-symptomatic COVID-19, so lets clarify these terms.
As we mentioned, an asymptomatic person goes through the whole course of their illness without developing symptoms. They may never even realize they were sick. The term pre-symptomatic meanwhile, refers to whats called an incubation period. Thats the time between getting infected and showing symptoms of an illness.
All viruses, including COVID-19, have an incubation period. In many cases, its when the virus is most contagious. While they are two different things, being pre-symptomatic and being asymptomatic are both tricky from a disease prevention standpoint because in both cases, a person can pass the virus on to other people without realizing theyre doing it.
Asymptomatic COVID-19 is quite common. Scientists think that at least 20% of all people infected with COVID-19 never have symptoms. Meanwhile, because COVID-19 reinfection is common and many of us have established some immunity to the virus its not unusual to experience both symptomatic and asymptomatic COVID-19 infections over the course of ones life.
At this stage in the pandemic, whether or not having COVID-19 will make you feel sick is, at least partially, a game of chance. But theres a growing body of evidence indicating that some of us are playing with loaded dice.
Studies indicate that children and adolescents may be more likely to have an asymptomatic infection than adults. Research also suggests that a lack of COVID-19 symptoms may sometimes be determined by genetics. That would make sense because we already know that some people are genetically predisposed to developing critical cases of COVID-19 pneumonia. These two branches of COVID-19-related research may one day help us limit the severity of symptoms in people who are prone to severe complications.
Dr. Dumford explains that not having symptoms of COVID-19 doesnt mean you cant infect other people. And the people you infect have the same risk of having symptoms that you did.
In other words, the virus youre passing on isnt different. Whats different is how your body responds.
Given that so many people with COVID show minimal to no symptoms, the possibility of exposure is present virtually every day, Dr. Dumford says. That makes preventive measures all the more important, especially if you or somebody you love is vulnerable to severe complications from COVID.
The U.S. Centers for Disease Control and Prevention (CDC) announced significant changes in COVID-19 isolation guidance on March 1, 2024. Their new policy says that isolation should be determined on the basis of clinical symptoms. That means you can end your isolation as soon as:
You see where this is going: People with asymptomatic COVID-19 infections now arent required to isolate at all. Its still encouraged to wear a well-fitting mask for the five days after coming out of isolation. If you dont have to isolate at all, Dr. Dumford says you should still strongly consider masking in public for five days after youre diagnosed.
Asymptomatic COVID-19 cases have always slipped through the net to a certain extent, even at the height of the pandemic. But in the past, many people had to submit to regular testing to attend work or school. Required testing is much rarer nowadays and many people are no longer able to isolate for five days without facing professional or academic consequences. The pandemic isnt over, but it sometimes feels like it is.
What does all this mean in practical terms?
Theres one other thing to be aware of: While its rare, some people with asymptomatic COVID-19 do go on to develop long COVID. In other words, they develop symptoms days, weeks or months after the virus resolves. And those symptoms continue for months or, in some cases, years.
Approximately 20% of individuals infected with COVID-19 are asymptomatic. That means they dont have any symptoms and may never even know they were sick. Thats a problem from a public health standpoint because the person who had COVID-19 is still contagious and can unknowingly spread the virus to other people. Its also reason #418 that staying up to date on your COVID-19 vaccines is so important.
If you know that you have an asymptomatic case of COVID-19, be sure that you wear a mask and practice social distancing if youre going to be around other people. Isolation guidelines are changing as the virus becomes part of our everyday lives, but your responsibility to protect others from infection isnt.
Just when you think its safe to go back into the grocery store, department store, restaurant, etc., etc., etc., of course a nasty respiratory illness has to come along and complicate your plans.
The culprit this time? You might have guessed it: COVID-19.
Yes, the scourge that made everyones lives that much more difficult beginning in 2020 is again on the rise in Hawaii.
COVID-19 is at the yellow, or medium activity level, meaning the virus is circulating at higher levels throughout the state than would be expected based on historic trends, and continuing to increase.
In Hawaii County, there were 129 new cases reported the week of May 14-20, the most recent data available. The Big Island is seeing a weekly average of 14 new cases a day.
The state saw an additional 659 new COVID cases reported the same week, with an weekly average of 71 new cases a day.
Case numbers are still updated once a week.
A rundown of the other counties for the week of May 14-20 shows:
Cases of the flu and respiratory syncytial virus, or RSV, remain at green statewide, or low activity levels.
Overall acute respiratory disease is at the medium level throughout the islands.
The latest levels of respiratory diseases and levels of infection come from the states new Repiratory Disease Dashboard.
The website was developed by the state Health Departments Disease Outbreak Control Division and provides an at-a-glance snapshot of respiratory disease activity statewide, including COVID-19.
The dashboard addresses not only COVID-19 but other acute respiratory illnesses such as influenza, or the flu, and RSV. Respiratory diseases occur year-round in the islands.
The new Respiratory Disease Dashboard provides, in one place, a summary of what is happening with several major respiratory viruses that contribute to respiratory disease in Hawaii, said State Epidemiologist Sarah Kemble This helps people make informed decisions about their health.
The dashboard shows that COVID testing positivity is higher than expected and climbing, Kemble added, with emergency room visits and hospital admissions increasing.
Based on this information, I would recommend checking whether youve had the 2023-24 COVID-19 vaccine, and if not, or if youre eligible for a repeat dose, go get it today, she said.
Dashboard trends show COVID remains a health concern, and the public should take reasonable precautions to avoid getting sick. Among them:
Additional strategies for reducing the spread of COVID and other respiratory disease can be found on the state Health Departments website.
You can visit the new Respiratory Disease Dashboard here.
May 28, 2024, 4:15 PM HST
Playing in :00
COVID-19 activity is on the rise, according to a new Respiratory Disease Activity dashboard released by the Hawaii State Department of Health (DOH).
The dashboard, developed by the DOH Disease Outbreak Control Division(DOCD), provides an at-a-glance snapshot of current respiratory disease activity statewide, including COVID-19. The dashboard addresses not only COVID-19, but other acute respiratory illnesses, including influenza (flu) and respiratory syncytial virus (RSV).Respiratory diseases occur year-roundin Hawaii.
Currently, COVID-19 is at the yellow, or medium activity level, meaning the virus is circulating at higher levels than would be expected based on historic trends. COVID-19 activity is also increasing. Flu and RSV remain at green, or low activity levels. Overall acute respiratory disease is at the medium level.
The new Respiratory Disease dashboard provides, in one place, a summary of what is happening with several major respiratory viruses that contribute to respiratory disease in Hawaii. This helps people make informed decisions about their health, said State Epidemiologist Sarah Kemble. This week, the dashboard shows that COVID-19 test positivity is higher than expected and climbing, and that ED (emergency department) visits and hospital admissions for COVID-19 are also going up. Based on this information, I would recommend checking whether youve had the 2023-24 COVID-19 vaccine, and if not, or if youre eligible for a repeat dose, go get it today.
Current dashboard trends show that COVID-19 remains a health concern, and the public should take reasonable precautions to avoid getting sick. Among them:
Additional strategies for reducing COVID-19 and other respiratory disease spread can be found athealth.hawaii.gov/docd.
Visit the new dashboardhere.
