McPherson, M., Smith-Lovin, L. & Cook, J. M. Birds of a feather: homophily in social networks. Annu. Rev. Sociol. 27(1), 415444. https://doi.org/10.1146/annurev.soc.27.1.415 (2001).
Article Google Scholar
Fu, F., Nowak, M. A., Christakis, N. A. & Fowler, J. H. The evolution of homophily. Sci. Rep. 2(1), 845. https://doi.org/10.1038/srep00845 (2012).
Article ADS CAS PubMed PubMed Central Google Scholar
Laniado, D., Volkovich, Y., Kappler, K. & Kaltenbrunner, A. Gender homophily in online dyadic and triadic relationships. EPJ Data Sci. 5(1), 19. https://doi.org/10.1140/epjds/s13688-016-0080-6 (2016).
Article Google Scholar
Campigotto, N., Rapallini, C. & Rustichini, A. School friendship networks, homophily and multiculturalism: evidence from European countries. J. Popul. Econ. 35(4), 16871722. https://doi.org/10.1007/s00148-020-00819-w (2022).
Article Google Scholar
Wlfer, R. & Hewstone, M. What buffers ethnic homophily? explaining the development of outgroup contact in adolescence. Dev. Psychol. 54(8), 15071518. https://doi.org/10.1037/dev0000547 (2018).
Article PubMed Google Scholar
Centola, D. An experimental study of homophily in the adoption of health behavior. Science 334(6060), 12691272. https://doi.org/10.1126/science.1207055 (2011).
Article ADS CAS PubMed Google Scholar
Pachucki, M. C. & Leal, D. F. Is having an educationally diverse social network good for health?. Netw. Sci. 8(3), 418444. https://doi.org/10.1017/nws.2020.14 (2020).
Article Google Scholar
Mark, N. Birds of a feather sing together*. Soc. Forces 77(2), 453485. https://doi.org/10.1093/sf/77.2.453 (1998).
Article Google Scholar
Boutyline, A. & Willer, R. The social structure of political echo chambers: variation in ideological homophily in online networks. Polit. Psychol. 38(3), 551569. https://doi.org/10.1111/pops.12337 (2017).
Article Google Scholar
Cinelli, M., De Francisci Morales, G., Galeazzi, A., Quattrociocchi, W. & Starnini, M. The echo chamber effect on social media. Proc. Natl. Acad. Sci. 118(9), 2023301118. https://doi.org/10.1073/pnas.2023301118 (2021).
Article CAS Google Scholar
Diaz-Diaz, F., San Miguel, M. & Meloni, S. Echo chambers and information transmission biases in homophilic and heterophilic networks. Sci. Rep. 12(1), 9350. https://doi.org/10.1038/s41598-022-13343-6 (2022).
Article ADS CAS PubMed PubMed Central Google Scholar
Aral, S., Muchnik, L. & Sundararajan, A. Distinguishing influence-based contagion from homophily-driven diffusion in dynamic networks. Proc. Natl. Acad. Sci. 106(51), 2154421549. https://doi.org/10.1073/pnas.0908800106 (2009).
Article ADS PubMed PubMed Central Google Scholar
Christakis, N. A. & Fowler, J. H. The spread of obesity in a large social network over 32 years. N. Engl. J. Med. 357(4), 370379. https://doi.org/10.1056/NEJMsa066082 (2007).
Article CAS PubMed Google Scholar
Christakis, N. A. & Fowler, J. H. The collective dynamics of smoking in a large social network. N. Engl. J. Med. 358(21), 22492258. https://doi.org/10.1056/NEJMsa0706154 (2008).
Article CAS PubMed PubMed Central Google Scholar
Shalizi, C. R. & Thomas, A. C. Homophily and contagion are generically confounded in observational social network studies. Sociol. Methods Res. 40(2), 211239. https://doi.org/10.1177/0049124111404820 (2011).
Article MathSciNet PubMed PubMed Central Google Scholar
Homans, G. C. Fifty years of sociology. Annu. Rev. Sociol. 12(1), xiii. https://doi.org/10.1146/annurev.so.12.080186.005033 (1986).
Article Google Scholar
Kandel, D. B. Homophily, selection, and socialization in adolescent friendships. Am. J. Sociol. 84(2), 427436. https://doi.org/10.1086/226792 (1978).
Article Google Scholar
Marks, S. R. Intimacy in the public realm: the case of co-workers. Soc. Forces 72(3), 843. https://doi.org/10.2307/2579783 (1994).
Article Google Scholar
Tulin, M., Mollenhorst, G. & Volker, B. Whom do we lose? The case of dissimilarity in personal networks. Soc. Netw. 65, 5162. https://doi.org/10.1016/j.socnet.2020.11.003 (2021).
Article Google Scholar
Blau, P. M. Structural Contexts of Opportunities (University of Chicago Press, Chicago, 1994).
Google Scholar
Mollenhorst, G., Vlker, B. & Flap, H. Social contexts and personal relationships: the effect of meeting opportunities on similarity for relationships of different strength. Soc. Netw. 30(1), 6068. https://doi.org/10.1016/j.socnet.2007.07.003 (2008).
Article Google Scholar
Feld, S. L. Social structural determinants of similarity among associates. Am. Sociol. Rev. 47(6), 797. https://doi.org/10.2307/2095216 (1982).
Article Google Scholar
McPherson, J. M. & Smith-Lovin, L. Homophily in voluntary organizations: status distance and the composition of face-to-face groups. Am. Sociol. Rev. 52(3), 370. https://doi.org/10.2307/2095356 (1987).
Article Google Scholar
Verbrugge, L. M. The structure of adult friendship choices. Soc. Forces 56(2), 576. https://doi.org/10.2307/2577741 (1977).
Article Google Scholar
McPherson, M. A Blau space primer: prolegomenon to an ecology of affiliation. Ind. Corp. Change 13(1), 263280. https://doi.org/10.1093/icc/13.1.263 (2004).
Article Google Scholar
Stauder, J. The social structure of opportunities for contact and interaction and strategies for analysing friendship networks. Der Partnermarkt und die Gelegenheiten des Kennenlernens: Der Partnermarktsurveyhttps://doi.org/10.1007/978-3-658-02794-0_11 (2014).
Article Google Scholar
Christakis, N. A. & Fowler, J. H. Social contagion theory: examining dynamic social networks and human behavior. Stat. Med. 32(4), 556577. https://doi.org/10.1002/sim.5408 (2013).
Article MathSciNet PubMed Google Scholar
Granovetter, M. S. The strength of weak ties. Am. J. Sociol. 78(6), 13601380. https://doi.org/10.1086/225469 (1973).
Article Google Scholar
Lin, N. A network theory of social capital. In The Handbook of Social Capita (eds Castiglione, D. et al.) 5069 (Oxford University Press, New York, NY, 2008).
Google Scholar
Marsden, P. V. & Campbell, K. E. Measuring tie strength. Soc. Forces 63(2), 482. https://doi.org/10.2307/2579058 (1984).
Article Google Scholar
Bidart, C., Degenne, A. & Grossetti, M. Living in Networks: The Dynamics of Social Relations 1st edn. (Cambridge University Press, Cambridge, 2020). https://doi.org/10.1017/9781108882392.
Book Google Scholar
Smith, K. P. & Christakis, N. A. Social networks and health. Annu. Rev. Sociol. 34(1), 405429. https://doi.org/10.1146/annurev.soc.34.040507.134601 (2008).
Article Google Scholar
Pampel, F. C., Krueger, P. M. & Denney, J. T. Socioeconomic disparities in health behaviors. Annu. Rev. Sociol. 36(1), 349370. https://doi.org/10.1146/annurev.soc.012809.102529 (2010).
Article PubMed PubMed Central Google Scholar
Rogers, E.M. Diffusion of Innovations, 5th Edition. Free Press, Place of publication not identified (2014). OCLC: 893102250
Phelan, J. C., Link, B. G. & Tehranifar, P. Social conditions as fundamental causes of health inequalities: theory, evidence, and policy implications. J. Health Soc. Behav. 51(1suppl), 2840. https://doi.org/10.1177/0022146510383498 (2010).
Article Google Scholar
Chang, V. W. & Lauderdale, D. S. Fundamental cause theory, technological innovation, and health disparities: the case of cholesterol in the era of statins. J. Health Soc. Behav. 50(3), 245260. https://doi.org/10.1177/002214650905000301 (2009).
Article PubMed PubMed Central Google Scholar
Correll, S. J. & Ridgeway, C. L. Expectation States Theory. In Handbook of Social Psychology (ed. Delamater, J.) 2951 (Springer, 2006).
Chapter Google Scholar
Strang, D. & Soule, S. A. Diffusion in organizations and social movements: from hybrid corn to poison pills. Annu. Rev. Sociol. 24(1), 265290. https://doi.org/10.1146/annurev.soc.24.1.265 (1998).
Article Google Scholar
Christakis, N. A. & Fowler, J. H. Social network sensors for early detection of contagious outbreaks. PLoS ONE 5(9), 12948. https://doi.org/10.1371/journal.pone.0012948 (2010).
Article ADS CAS Google Scholar
Konstantinou, P. et al. Transmission of vaccination attitudes and uptake based on social contagion theory: a scoping review. Vaccines 9(6), 607. https://doi.org/10.3390/vaccines9060607 (2021).
Article CAS PubMed PubMed Central Google Scholar
Hao, F. & Shao, W. Understanding the influence of political orientation, social network, and economic recovery on COVID-19 vaccine uptake among Americans. Vaccine 40(14), 21912201. https://doi.org/10.1016/j.vaccine.2022.02.066 (2022).
Article CAS PubMed PubMed Central Google Scholar
Fu, L. Y., Zimet, G. D., Latkin, C. A. & Joseph, J. G. Social networks for human papillomavirus vaccine advice among African American parents. J. Adolesc. Health 65(1), 124129. https://doi.org/10.1016/j.jadohealth.2019.01.029 (2019).
Article PubMed PubMed Central Google Scholar
Casillas, A. et al. The impact of social communication on perceived HPV vaccine effectiveness in a low-income, minority population. Ethn. Dis. 21(4), 495501 (2011).
PubMed Google Scholar
Edge, R., Keegan, T., Isba, R. & Diggle, P. Observational study to assess the effects of social networks on the seasonal influenza vaccine uptake by early career doctors. BMJ Open 9(8), 026997. https://doi.org/10.1136/bmjopen-2018-026997 (2019).
Article Google Scholar
Hiraoka, T., Rizi, A. K., Kivel, M. & Saramki, J. Herd immunity and epidemic size in networks with vaccination homophily. Phys. Rev. E 105(5), 052301. https://doi.org/10.1103/PhysRevE.105.L052301 (2022).
Article ADS MathSciNet Google Scholar
Mossong, J. et al. Social contacts and mixing patterns relevant to the spread of infectious diseases. PLoS Med. 5(3), 74. https://doi.org/10.1371/journal.pmed.0050074 (2008).
Article Google Scholar
Takahashi, S., Metcalf, C. J. E., Ferrari, M. J., Tatem, A. J. & Lessler, J. The geography of measles vaccination in the African Great Lakes region. Nat. Commun. 8(1), 15585. https://doi.org/10.1038/ncomms15585 (2017).
Article ADS CAS PubMed PubMed Central Google Scholar
Danis, K., Georgakopoulou, T., Stavrou, T., Laggas, D. & Panagiotopoulos, T. Predictors of childhood vaccination uptake: a cross-sectional study in Greece. Proc. Vaccinol. 2(1), 8691. https://doi.org/10.1016/j.provac.2010.03.016 (2010).
Article Google Scholar
Larson, H. J., Jarrett, C., Eckersberger, E., Smith, D. M. D. & Paterson, P. Understanding vaccine hesitancy around vaccines and vaccination from a global perspective: a systematic review of published literature, 20072012. Vaccine 32(19), 21502159. https://doi.org/10.1016/j.vaccine.2014.01.081 (2014).
Article PubMed Google Scholar
Burgio, G., Steinegger, B. & Arenas, A. Homophily impacts the success of vaccine roll-outs. Commun. Phys. 5(1), 17. https://doi.org/10.1038/s42005-022-00849-8 (2022).
Article Google Scholar
Ajzen, I. The theory of planned behavior. Organ. Behav. Hum. Decis. Process. 50(2), 179211. https://doi.org/10.1016/0749-5978(91)90020-T (1991).
In January 2020, a man who would become known as the first documented Covid-19 patient in the United States arrived at an urgent care clinic.
Two of his symptoms, a cough and a fever, were among those that would become known as the telltale symptoms of Covid. But the patient had also experienced two days of nausea and vomiting.
Many of us associate Covid with respiratory issues. But some people who get sick with the virus never experience a sore throat, coughing or body aches, said Dr. Peter Chin-Hong, an infectious disease specialist at the University of California, San Francisco. Certain people end up feeling more like they have food poisoning than anything else.
Thats because coronavirus is like throwing a bomb in your body, said Dr. Ken Cadwell, a professor of medicine at the University of Pennsylvania who studies how Covid affects the gut. Youre going to feel that in multiple different organs, not just the lungs.
With Covid cases climbing, and the so-called FLiRT variants fueling yet another summer spread, heres how to spot, and address, the lesser-known gastrointestinal symptoms.
In some people, gastrointestinal symptoms hit during the first few days of an infection, before they develop a fever and cough. But many people who only experience stomach symptoms never think of it as Covid, Dr. Chin-Hong said.
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As part of wide-ranging job cuts, Oregon Health & Science University this week cut a telehealth nursing unit set up during the COVID-19 pandemic that was featured on the OHSU Foundation website for its service to people across the state.
OHSU started the Connected Care Center on March 30, 2020, just as the pandemic began. It was open only to OHSU patients before opening to the public shortly afterward. Nurses worked from home, taking calls about testing locations, quarantining, and care for the disease, according to a June 2021 write-up by OHSU.
Since the pandemic, the 16 nurses in the unit had been supporting OHSUs clinics and triaging patient calls, according to an employee who wished to remain anonymous.
OHSU is in the midst of cutting some 500 positions, including nurses, as part of a strategic alignment despite repeated vows from management to spare most patient-facing employees.
Cutting nurses is confirmation that OHSU executives will not limit their layoffs to non-patient-facing positions, said Duncan Zevetski, a registered nurse and vice president at the Oregon Nurses Association, which represents 4,500 OHSU employees. Their cuts will reduce Oregonians access to care and ultimately make it harder for more people to get the care they need when they need it.
OHSU has cut a total of 22 nurses in recent days, the union said.
The layoffs come as OHSU pursues a merger with Legacy Health, another hospital system that is struggling with high costs for salaries and supplies.
The strategic alignment work aims to shift OHSUs overall strategy to its core, state-mandated missions, including improving access to the complex specialty and subspecialty services that no other health system in the region can provide, university spokeswoman Sarah Hottman said in an email. As a result, while planned reductions in force are largely administrative roles, other programs may be impacted as well.
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DALLAS Medical City Healthcare is warning North Texans ahead of Fourth of July gatherings that cases of COVID-19 have been on the rise in recent weeks.
According to Medical City Healthcare, positive cases have doubled in the past month and despite low hospitalization rates, the community must remain vigilant to the virus.
"Our community is experiencing a rise in COVID-19 cases," Chief Medical Officer Dr. Joseph Parra said. "While hospitalizations remain low, we are seeing notable increases in respiratory virus indicators, particularly at our CareNow clinics, which provide rapid testing for non-emergency cases."
Medical City says the Texas Department of State Health Services reported a 19.4% increase in cases in week 24 statewide.
Parra encourages everyone to take the following preventative measures:
Medical City says patients with underlying medical conditions are at higher risk of having a severe COVID-19 infection that may include symptoms like trouble breathing, persistent chest pain, confusion, and pale grey skin and lips.
To learn more about COVID-19, vaccinations and more, visit here.
ALIOUI Mohammed Elamine/ iStock
People who have long COVID symptomsthose that linger well after the initial SARS-CoV-2 infectioncan display signs of abnormal immune-cell activation in many of their organs and tissues, as well as leftover SARS-CoV-2 RNA in the gut, for more than 2 years after infection, according toa small study this week in Science Translational Medicine.
University of California, San Francisco researchers analyzed data on 24 people after their initial COVID-19 illness who underwent whole-body positron emission tomography (PET) imagingat time points ranging from 27 to 910 days (about 2 and a half years) after their acute COVID-19 cases. Eighteen of the patients had long COVID.
The team used a tracer during PET imaging that selectively tags activated T cells and found that people with long COVID had certain tissues that were enriched for activated T cells in comparison with never-infected people who did not have long COVID (prepandemic controls).
Furthermore, this T-cell activation correlated with symptoms of long COVID. For example, people who reported persistent lung problems had stronger signs of T-cell immune activation in their lungs.
In addition, because the gut was one of the sites of activated T-cell enrichment, the scientists analyzed colorectal biopsies from five of the patients with long COVID. All five of these samples contained SARS-CoV-2 RNA.
The authors wrote, "In this first-in-human T cell activation PET imaging study of individuals after SARS-CoV-2 infection, we found evidence of persistent T cell activation in a variety of tissues. In some individuals, this activity may persist for years after initial COVID-19 onset and be associated with systemic changes in immune activation as well as the presence of [long COVID] symptoms."
"Overall, these observations challenge the paradigm that COVID-19 is a transient acute infection, building on recent observations in blood," the authors concluded.
Throughout the pandemic, one of the key questions on everyones mind was why some people avoided getting COVID while others caught the virus multiple times.
Through a collaboration between University College London, the Wellcome Sanger Institute, and Imperial College London in the UK, we set out to answer this question using the worlds first controlled challenge trial for COVID where volunteers were deliberately exposed to SARS-CoV-2, the virus that causes COVID so that it could be studied in great detail.
Unvaccinated healthy volunteers with no prior history of COVID-19 were exposed via a nasal spray to an extremely low dose of the original strain of SARS-CoV-2. The volunteers were then closely monitored in a quarantine unit, with regular tests and samples taken to study their response to the virus in a highly controlled and safe environment.
For our recent study, published in Nature, we collected samples from tissue located midway between the nose and the throat as well as blood samples from 16 volunteers. These samples were taken before the participants were exposed to the virus, to give us a baseline measurement, and afterwards at regular intervals.
The samples were then processed and analyzed using single-cell sequencing technology, which allowed us to extract and sequence the genetic material of individual cells. Using this cutting-edge technology, we could track the evolution of the disease in unprecedented detail, from pre-infection to recovery.
To our surprise, we found that, despite all the volunteers being carefully exposed to the exact same dose of the virus in the same manner, not everyone ended up testing positive for COVID.
In fact, we were able to divide the volunteers into three distinct infection groups (see illustration). Six out of the 16 volunteers developed typical mild COVID, testing positive for several days with cold-like symptoms. We referred to this group as the sustained infection group.
Out of the ten volunteers who did not develop a sustained infection, suggesting that they were able to fight off the virus early on, three went on to develop an intermediate infection with intermittent single positive viral tests and limited symptoms. We called them the transient infection group.
The final seven volunteers remained negative on testing and did not develop any symptoms. This was the abortive infection group. This is the first confirmation of abortive infections, which were previously unproven. Despite differences in infection outcomes, participants in all groups shared some specific novel immune responses, including those whose immune systems prevented the infection.
When we compared the timings of the cellular response between the three infection groups, we saw distinct patterns. For example, in the transiently infected volunteers where the virus was only briefly detected, we saw a strong and immediate accumulation of immune cells in the nose one day after infection.
This contrasted with the sustained infection group, where a more delayed response was seen, starting five days after infection and potentially enabling the virus to take hold in these volunteers.
In these people, we were able to identify cells stimulated by a key antiviral defense response in both the nose and the blood. This response called the interferon response, is one of the ways our bodies signal to our immune system to help fight off viruses and other infections. We were surprised to find that this response was detected in the blood before it was detected in the nose, suggesting that the immune response spreads from the nose very quickly.
Lastly, we identified a specific gene called HLA-DQA2, which was expressed (activated to produce a protein) at a much higher level in the volunteers who did not go on to develop a sustained infection and could hence be used as a marker of protection. Therefore, we might be able to use this information to identify those who are probably going to be protected from severe COVID.
These findings help us fill in some gaps in our knowledge, painting a much more detailed picture regarding how our bodies react to a new virus, particularly in the first couple of days of an infection, which is crucial.
We can use this information to compare our data to other data we are currently generating, specifically where we are challenging volunteers to other viruses and more recent strains of COVID. In contrast to our current study, these will mostly include volunteers who have been vaccinated or naturally infected that is, people who already have immunity.
Our study has significant implications for future treatments and vaccine development. By comparing our data to volunteers who have never been exposed to the virus with those who already have immunity, we may be able to identify new ways of inducing protection, while also helping the development of more effective vaccines for future pandemics. In essence, our research is a step towards better preparedness for the next pandemic.
This article was originally published on The Conversation by Marko Nikolic and Kaylee Worlock at UCL. Read the original article here.
Bird flu
Colorado dairy worker recovers as officials work toward vaccines and offer farmers financial aid
The US announced its fourth human case of bird flu, in a Colorado dairy worker, on Wednesday, as officials work to expand the availability of potential vaccines and commercial tests and open up financial assistance for affected farmers.
The dairy worker was in close contact with cows that had tested positive for H5N1, a highly pathogenic bird flu, and the worker reported only eye symptoms, according to the Centers for Disease Control and Prevention (CDC).
The person took antiviral medication and has recovered, the CDC said. The agency is sequencing a sample of the virus to see if it has developed any concerning mutations.
More than 780 people have been monitored for symptoms and at least 53 have been tested for H5N1 this year, the CDC reports. The vast majority of those tests have been performed in Michigan.
Colorado has the highest number of affected herds, according to the US Department of Agriculture (USDA). A cat in Colorado has also tested positive after no known contact with poultry or dairy operations.
Prior to this years outbreak in dairy cattle, the only previous US case in humans was detected in Colorado in 2022, after an incarcerated person was exposed to the virus while culling a flock of infected poultry.
The new case followed an announcement the day before from US officials about plans to build up the supply of H5N1 vaccines and expand the availability of tests.
The US is partnering with the vaccine maker Moderna to help develop and manufacture mRNA bird flu vaccines if needed, said Dawn OConnell, assistant secretary for preparedness and response (ASPR). Trials for safety and efficacy in people would probably begin next year, she said.
While the $176m contract focuses on H5N1 vaccines, it could also be used on developing or procuring vaccines targeting other strains of influenza or emerging infectious diseases, McConnell said.
The US has also ordered 4.8m doses of another type of H5N1 vaccine, which are expected to come off the production line in the middle of July, faster than we had initially anticipated, McConnell said.
These vaccines would still need to be approved by the Food and Drug Administration (FDA) before they could be given to people.
The risk to humans from bird flu remained low, officials said, and H5N1 vaccines are not recommended for anyone at this point.
Officials also floated the possibility of using influenza antivirals to prevent transmission of the H5N1 virus among people, if it mutates to become more effective at human-to-human spread.
The vaccines tend to be better at preventing severe disease rather than transmission, said Nirav Shah, principal deputy director of the CDC, adding that more widespread distribution of antivirals could help with the latter.
Expanding test availability could mean those at risk for contracting H5N1 could go to a commercial lab to get tested, which could make testing more accessible and faster.
Right now, the US has about 750,000 tests for H5N1, and another 1.2m expected in the next two to three months, all of which are conducted in public health laboratories. The CDC is working to share its test designs with commercial companies, and on 10 June the agency opened a call for companies to propose new H5N1 test designs.
On Monday, the USDA opened up a financial assistance program to dairy producers with herds affected by H5N1. While infected cows usually survive, their milk production often plummets, and disposing of H5N1-infected milk means lost income.
The new program allows any dairy farmers with H5N1-positive cows to apply for federal assistance, similar to programs that exist for poultry farmers who lose flocks. Experts hope it will encourage producers to test their herds and help contain the spread of bird flu.
Six states have also enrolled in the USDAs voluntary dairy herd status pilot program, and 24 herds are enrolled in the agencys financial support programs to enhance biosecurity and testing on farms.
Bird flu vaccines for cows are also being studied, but that process takes time, said Eric Deeble, acting senior adviser for the USDAs H5N1 response. It will take a while for any vaccine to become available, and in the interim, were going to continue to stress biosecurity for example, limiting the number of people on farms, or cleaning and disinfecting equipment and clothing. Studies so far indicate that people are moving the virus between farms via shared workers, cows, vehicles and equipment.
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Federal officials suspect that live bird markets in San Francisco may be the source of bird flu virus in area wastewater samples.
Days after health monitors reported the discovery of suspected avian flu viral particles in wastewater treatment plants, federal officials announced that they were looking at poultry markets near the treatment facilities.
Last month, San Francisco Public Health Department officials reported that state investigators had detected H5N1 the avian flu subtype making its way through U.S. cattle, domestic poultry and wild birds in two chickens at a live market in May. They also noted they had discovered the virus in city wastewater samples collected during that period.
Two new hits of the virus were recorded from wastewater samples collected June 18 and June 26 by WastewaterSCAN, an infectious-disease monitoring network run by researchers at Stanford, Emory University and Verily, Alphabet Inc.s life sciences organization.
Nirav Shah, principal deputy director of the U.S. Centers for Disease Control and Prevention, said that although the source of the virus in those samples has not been determined, live poultry markets were a potential culprit.
Hits of the virus were also discovered in wastewater samples from the Bay Area cities of Palo Alto and Richmond. It is unclear if those cities host live bird markets, stores where customers can take a live bird home or have it processed on-site for food.
Steve Lyle, a spokesman for the states Department of Food and Agriculture, said live bird markets undergo regular testing for avian influenza.
He said that aside from the May 9 detection in San Francisco, there have been no other positives in Live Bird Markets throughout the state during this present outbreak of highly-pathogenic avian flu.
San Franciscos health department referred all questions to the state.
Even if the state or city had missed a few infected birds, John Korslund, a retired U.S. Department of Agriculture veterinarian epidemiologist, seemed incredulous that a few birds could cause a positive hit in the citys wastewater.
Unless youve got huge amounts of infected birds in which case you ought to have some dead birds, too itd take a lot of bird poop to become detectable in a citys wastewater system, he said.
But the question still remains: Has anyone done sequencing? he said. It makes me want to tear my hair out.
He said genetic sequencing would help health officials determine the origin of viral particles whether they came from dairy milk, or from wild birds. Some epidemiologists have voiced concerns about the spread of H5N1 among dairy cows, because the animals could act as a vessel in which bird and human viruses could interact.
However, Alexandria Boehm, professor of civil and environmental engineering at Stanford University and principal investigator and program director for WastewaterSCAN, said her organization is not yet able to reliably sequence H5 influenza in wastewater. We are working on it, but the methods are not good enough for prime time yet.
A review of businesses around San Franciscos southeast wastewater treatment facility indicates a dairy processing plant as well as a warehouse store for a member-supported community of people that feed raw or cooked fresh food diets to their pets.
Raw milk can harbor live bird flu virus, according to the results of a new study. The results come ... [+] amid a survey showing that many Americans underestimate the health risks of consuming raw milk.
An alarming 14% of raw milk samples taken from four states with dairy herd outbreaks contained infectious H5N1 bird flu, according to new testing results released by the FDA.
The researchers took 275 milk samples from bulk storage tanks on farms in states where dairy cattle are confirmed to be infected by H5N1. The virus was actually detected in 57.5% of the samples, with further testing showing that a quarter of these contained infectious virus. However, the FDA was keen to stress that the study was not specifically designed to assess the prevalence of the virus in milk and that the numbers might not be more widely representative.
"The goal of this study was to determine what range of viral load might be present in raw milk samples from farms that routinely send product for pasteurization, not to determine state-wide or national H5N1 virus prevalence in the overall milk supply," said a spokesperson for the FDA.
The results were published in a preprint paper, which has not yet been peer reviewed by external experts for scientific rigor. However, the paper has sparked a significant response from experts around the world, reiterating the dangers of consuming raw milk.
The researchers also artificially spiked milk with infectious H5N1 virus, before heat treating it in a process designed to mimic pasteurization, which the standard commercial milk supply goes through before sale, finding that the process was very effective at inactivating the virus. "These findings demonstrate that the milk supply is safe," the researchers stated.
The consumption of raw milk, which has not undergone filtration or heat treatment to remove pathogens, has been responsible for several outbreaks of illness including with bacteria such as campylobacter and comes with significant health risks, according to the CDC. Although there are no documented cases yet of humans getting H5N1 by drinking infected raw milk, there is evidence that mice have been infected via drinking cows milk.
However, all of the milk sampled for the FDA study was destined to be pasteurized.
"The samples in this study were taken from milk producers participating in the Pasteurized Milk Ordinance (PMO) regulatory program and thus their milk was bound for pasteurization and not destined for sale to consumers as raw milk in states where this is permitted," said a spokesperson for the FDA.
The new results come amid a new survey released today which shows that less than half of U.S. adults know that drinking raw milk is more unsafe than drinking milk that has been pasteurized.
The survey, run by researchers at the Annenberg Public Policy Center at the University of Pennsylvania from June 7-10, asked more than 1,000 U.S. adults their beliefs about raw milk, finding that only 47% of respondents knew that raw milk was less safe to drink. A further 30% were not sure, 15% thought it was just as safe and 9% of respondents thought it was safer.
It is important that anyone planning to consume raw milk be aware that doing so can make you sick and that pasteurization reduces the risk of milk-borne illnesses, said Patrick E. Jamieson, director of the Annenberg Health and Risk Communication Institute at the Annenberg Public Policy Center at the University of Pennsylvania.
The survey also found that 20% of respondents weren't sure how effective pasteurization is at killing viruses and bacteria and 4% thought it was "not too effective" or "not at all effective." Adults who were 65 or older and/or college educated were more likely to understand the benefits of pasteurization and also correctly believe that pasteurization does not destroy nutrients in milk.
Some beliefs about raw milk were also different depending on political affiliation, with 57% of Democrats believing that drinking raw milk is more unsafe than drinking pasteurized milk, compared to 37% of Republicans.
"The difference in views of raw milk that we see between Democrats and Republicans is difficult to disentangle from the difference between rural and urban dwellers, said Kathleen Hall Jamieson, director of the Annenberg Public Policy Center. Those in rural areas are both more likely to identify as Republicans and to consume raw milk.
This article was updated on 3rd July at 4pm EST to include comments from the FDA regarding the study.
