News Scan for Jun 29, 2016

News brief

Phase 3 study shows HPV vaccine effective for women over 26

The human papillomavirus (HPV) 16/18 vaccine (Cervarix) is safe and effective when administered to older adult women after 7 years of follow-up. That's the takeaway from the VIVIANE study, which tracked 10,000 women worldwide who received the vaccine after the age of 26.

The vaccine was protective against persistent infections and cervical abnormalities associated with HPV types 16 and 18, as well as infections with non-vaccine HPV types 31 and 45, researchers report in The Lancet Infectious Diseases. HPV infection causes 85% of invasive cervical cancer, and many countries administer HPV vaccines to girls ages 9 to 13 to effectively limit the burden of disease.

The investigators determined these efficacies 7 years after vaccination: 90.5% in the according-to-protocol cohort, 86.5% in the total vaccinated cohort, and 56.8% in the total vaccine cohort against 6-month persistent infection or CIN1+ (cervical premalignancy).

The study also reports the vaccine was 88.1% effective in protecting against infection with HPV 16 and 18 at a 6-month endpoint, and 70% effective against HPV types 31 and 45, which aren't targeted by GlaxoSmithKline's Cervarix. But the vaccine was only 35.8% effective against C1N2+ (advanced cervical dysplasia, a precursor to cervical cancer) at the 7-year follow-up. This was expected, the authors said, as the study included women with prevalent HPV infection at the time of initial vaccination.

Still, the study suggests that women age 26 or older would benefit from receiving the HPV vaccine, especially in countries where access to regular Pap smears is limited.
Jun 28 Lancet Infect Dis study

Neuropsychological symptoms seen years after West Nile infection

Infection with West Nile virus (WNV) can cause lasting neuropsychological challenges for patients, and these symptoms can linger for 2 to 4 years, according to a study yesterday in PLoS One.

Canadian researchers used a battery of psychological tests on 49 patients with confirmed WNV infection. Seventeen had neuroinvasive disease (encephalitis, meningitis, or meningo-encephalitis), while 32 had non-neuroinvasive WNV fever.

The neuropsychological test results were similar between the two groups. A substantial percentage of patients had impaired motor functioning (28% to 42%), verbal learning and memory (11% to 36%), and some measures of executive functioning (11% to 30%). Visual learning and memory, information processing speed, visual-spatial ability, and attention were affected at lower rates. This suggests that neuropsychological damage from WNV is systemic, and not exclusively linked to neuroinvasive forms of WNV infection, the authors wrote.

Duration of the illness—not disease presentation or severity—was linked to more cognitive difficulties. Patients infected with WNV within 6 months or less were less likely to have cognitive impairments than those who had been infected for 2 years or longer.

"We anticipate that data from this study will inform patients and their healthcare providers about the expected course of recovery, and will help prepare patients and caregivers to seek suitable supports beyond the initial recovery period," the authors said.
Jun 28 PLoS One study

Two norovirus vaccine candidates shown safe, immunogenic in adults

The Journal of Infectious Disease yesterday published an encouraging study of two norovirus vaccine candidates. Both VLP (virus-like particle) vaccines elicited a strong immune response and were safe when administered to healthy adults.

Norovirus, which can cause severe vomiting and diarrhea, is a significant public health threat, especially among elderly and immune-compromised populations. Because transmission of norovirus is often unpredictable, a vaccine could be useful in limiting disease outbreaks.

A total of 454 study volunteers ages 18 to 49 received either a placebo injection, or vaccines containing either GI.1 genotype VLP or GII.4 VLP. The GI.1 vaccine was based on the original Norwalk virus, and the GII.4 vaccine derived from three strains of norovirus.

Both vaccines tested elicited a strong immune response 7 to 10 days after injection, with the response lasting through day 28.

None of the study volunteers reported significant adverse events or reactions to either vaccine, but about 20% of volunteers receiving either injection reported transient muscle soreness.
Jun 28 J Infect Dis study

Flu Scan for Jun 29, 2016

News brief

H5N1 strikes Nigerian poultry farm, Chinese zoo lions

Nigeria's agriculture ministry yesterday reported an H5N1 avian flu outbreak at a commercial farm in Lagos state, and authorities in China said H5N1 has been detected in lions at a zoo in Hubei province.

The outbreak in Nigeria began on Jun 22, striking a facility that housed 3-week-old pullets, according to a report posted yesterday by the World Organization for Animal Health (OIE). Of 4,000 susceptible birds, the virus killed 1,355 and the remaining poultry were destroyed to curb the spread of the virus. Officials said poor biosecurity likely played a role in the event, though investigators haven't pinpointed the source of the outbreak.

Nigeria is among a handful of African countries that have reported a recurrence of H5N1 outbreaks in poultry after a several-year hiatus.
Jun 28 OIE report

Notification of China's detection of H5N1 in African lions kept at a zoo in the Hubei province city of Ezhou was made in a statement from the provincial government that was translated and posted by Avian Flu Diary, an infectious disease news blog.

Testing was triggered by illness in two African lions who had high fevers. After veterinary officials isolated and began to treat the lions, the male lion suddenly died and a female recovered. No similar illnesses have been seen in the zoo's other animals.

Testing of samples from the lions at a military veterinary hospital was positive for H5N1. Among other response measures, the park's birds were vaccinated against the virus.

The detection is the first known H5N1 infection in lions, though China reported fatal infections in tigers in 2014 and 2015, and Indonesia in 2006 reported H5N1 antibodies in stray cats.
Jun 29 Avian Flu Diary post

WHO: South America, southern Africa are main flu hot spots

South America and southern Africa have reported steady rises in flu activity over the past few weeks, but disease activity is rising more slowly in other Southern Hemisphere countries such as Australia, the World Health Organization (WHO) said in its latest global flu update.

The 2009 H1N1 virus and respiratory syncytial virus (RSV) are the main viruses detected in South America, but influenza B is predominant in southern African countries.

In South America, flu activity in Brazil seems to have peaked earlier than usual and at a high level that was similar to 2013, when 2009 H1N1 was the dominant strain. Of Brazil's deaths from severe respiratory infection, almost 71% of patients had underlying health conditions, the WHO said. Elsewhere, flu levels increased in Bolivia and Colombia.

In contrast, flu levels in Australia were at or just above baseline levels, with New Zealand also reporting low flu activity.

Flu activity from 2009 H1N1 is still under way in some parts of Central America, with levels rising in Panama, the WHO reported. In Africa, flu is increasing steadily in temperate southern regions.

Other parts of the world are seeing low flu activity, including the Caribbean countries, other parts of Africa, Asian countries, North America, and Europe.

At the global level, influenza A was responsible for about 60% of flu detections, and of the subtyped "A" strains, 86% were the 2009 H1N1 virus while the rest were H3N2, according to the WHO.
Jun 27 WHO global flu update