Experts say focus on surveillance, not genomes for pandemic readiness
Spending public health money on surveillance rather than on broad, expensive genomic surveys of animal diseases is a sounder investment and better way to prepare for the next pandemic or other global health emergency, three infectious disease experts wrote today in Nature.
"The resurgence of Ebola virus in the Democratic Republic of the Congo this May is a stark reminder that no amount of DNA sequencing can tell us when or where the next virus outbreak will appear," they write, noting that more genome sequence data were obtained in the 2014-16 Ebola outbreak in West Africa than for any single epidemic.
The experts—Edward C. Holmes, PhD, of the University of Sydney, Andrew Rambaut, PhD, of the University of Edinburgh, and Kristian G. Andersen, PhD, at The Scripps Research Institute—also maintain that overselling the potential of genome sequencing to predict future outbreaks undermines trust in public health.
They highlight the recently announced Global Virome Project and its $1.2 billion price tag, which is about a fourth of the annual infectious disease research budget of the US National Institute of Allergy and Infectious Diseases. "Broad genomic surveys of animal viruses will almost certainly advance our understanding of virus diversity and evolution," they write. "[But] in our view, they will be of little practical value when it comes to understanding and mitigating the emergence of disease.
"We urge those working on infectious disease to focus funds and efforts on a much simpler and more cost-effective way to mitigate outbreaks—proactive, real-time surveillance of human populations." They add that emerging diseases are often tied to factors like human encroachment on animal habitat, environmental disturbances, and climate change.
Jun 7 Nature commentary
Study: Influenza remains infective regardless of humid levels
A study today in the Journal of Infectious Diseases challenges the long-held notion that the influenza virus loses infectivity as humidity levels increase.
The study used humidity-controlled chambers to measure the stability of the 2009 pandemic influenza A(H1N1) virus in suspended aerosols and stationary droplets during a 1-hour challenge.
Using a rotating drum that suspended aerosols, the team combined samples of human airway secretions with the 2009 pandemic H1N1 flu strain. When sprayed into a drum, this mixture mimicked the mucosal spray of a sick person's cough.
The drum was tested at seven different humidity levels, ranging from arid to tropical. In all levels, infectivity remained stable.
"The result was surprising," said Linsey C. Marr, PhD, of Virginia Tech's Department of Civil and Environmental Engineering, in a University of Pittsburgh press release. "Because our previous work suggested that the flu virus survived better at low humidity. We thought this might help explain why flu season occurs in the winter, when humidity is low indoors, but we now have to rethink what's happening with the virus when it's in droplets and aerosols."
Jun 7 Journal of Infect Dis study
Jun 7 University of Pittsburgh press release
Officials adjust Nipah totals, say outbreak contained
After testing 244 samples, health officials confirmed 18 cases of Nipah virus, 16 of them fatal, in India's Kerala state, NDTV reported today. The health ministry said the totals were adjusted after two samples from suspected cases that initially tested positive, now tested negative for Nipah.
Earlier this week the chief minister of Kerala Pinarayi Vijayan said the outbreak was contained, telling NDTV, "There is no alarming situation now. The spread of the virus has been controlled. But people should remain alert."
The Nipah outbreak began in early May, when two brothers died from the rare virus. A nurse at a Kerala hospital also died after treating patients who were infected with the virus.
Officials said bats are not ruled out as the primary source of the outbreak, despite samples from seven bat species testing negative for the virus, WION reported today. Local pigs and cattle have also tested negative.
New samples from 55 fruit bats are currently being tested, and officials explained that these animals could likely be the reservoir of the deadly virus. Fruit bats harbor Nipah infections only for a short time, which makes testing difficult, officials said.
Jun 7 NDTV story
Jun 4 NDTV story
Jun 7 WION story
Study: When measles vaccine fails to protect, symptoms milder
A study of measles cases in California over 16 years has revealed that 80% of patients were unvaccinated, 9% had had one dose of measles vaccine, and 11% had had two or more doses of measles vaccine, with this final group experiencing less severe illness. The study was published today in Clinical Infectious Diseases.
Two doses of the measles, mumps, and rubella vaccine are designed to provide protection against measles, so a case in a patient receiving that regimen is considered vaccine failure.
The study authors reviewed all 232 measles cases reported to the California Department of Public Health from 2000 through 2015. They found that individuals who had received two or more vaccine doses had lower rates of hospitalization, cough, coryza (cold-like symptoms), conjunctivitis, and fever than patients who had one vaccine dose or were unimmunized.
The authors conclude, "Vaccine failure measles cases were less ill than cases that occurred in unvaccinated patients. Nevertheless, these cases still required the same amount of public health effort in tracing contacts as in cases who were unvaccinated."
Jun 7 Clin Infect Dis abstract