Reports detail early start to West Nile season in Europe
Some European countries this year experienced an early start to their West Nile virus (WNV) transmission season, which could be related to earlier warmer temperatures and higher rainfall levels that foster populations of Culex mosquitoes that carry the virus, according to two reports published today in the latest issue of Eurosurveillance.
In the first study, focused just on Italian surveillance, researchers said the first human case was reported in the endemic province of Rovigo, in Veneto region, in the middle of June. They note that the first cases are usually seen in July, with case numbers peaking in August and September. Also, they said human cases are higher than in previous years. As of Aug 1, 52 human WNV infections had been reported in two regions. The cases include 16 neuroinvasive illnesses, 14 involving West Nile fever, and 22 with asymptomatic infections.
In recent years, transmission patterns have been changing for other vectorborne diseases in Europe, and climate change has been implicated as a contributing factor, the group wrote. They said the One Health surveillance system in Italy is providing an early-warning service, which allowed blood and tissue donation safety measures to be stepped up before the first human cases were reported.
In the second report, a team led by the European Centre for Disease Prevention and Control (ECDC) detailed early West Nile virus activity in Italy along with Greece, Hungary, and Romania.
The investigators said the first cases of 2018 were reported from Greece in late June and early July, with May 31 as the earliest illness onset. In other European countries, the authors also saw a steeper rise in cases, with 168 cases reported in the first 6 weeks of the season compared with 8, 2, 62, and 66 in 2014 through 2017, respectively.
Climate data show that precipitation was above average in March, especially in West Nileaffected areas, followed by warmer-than-average temperatures with normal rainfall in April and warmer temperatures in May, with precipitation levels along the Adriatic coast high in May and June.
They authors concluded that the weather pattern reflects an early spring in southeastern Europe, which could favor an early rise in vector populations. The early season should trigger heightened vigilance for the disease for clinicians. They note that outbreaks depend on numerous factors, and an early start to the season doesn't necessarily mean large outbreaks will occur.
Aug 9 Eurosurveill report on early West Nile virus season in Italy
Aug 9 Eurosurveill report on early West Nile activity in Europe
More H5 outbreaks reported in Russian, Taiwanese poultry
In the latest highly pathogenic H5 avian flu developments, Russia reported eight more outbreaks in backyard birds and Taiwan reported a pair of H5N2 events, according to the latest notifications from the World Organization for Animal Health (OIE).
In Russia, the outbreaks are part of ongoing activity, which European officials have reported as H5N8, that has been under way in the west of the country since June. The latest outbreaks all involved backyard poultry, with start dates that ranged from Jul 25 to Aug 5. Affected locations include Orlov and Nizhegorod oblasts and the Chuvash, Udmurt, and Mari El republics.
Taken together, the virus killed 68 of 598 susceptible birds, and the surviving poultry were culled as part of the outbreak response.
Taiwan's latest H5N2 outbreaks are part of virus activity that's been under way since early 2015. The two new events both affected commercial farms in Yunlin County, one that began on Jul 18 at a meat duck farm and one that began on Jul 27 at facility housing native chickens.
Between the two outbreaks, 3,811 poultry deaths were reported, and authorities destroyed the remaining 36,055 birds to curb the spread of the virus.
Aug 8 OIE report on H5 in Russia
Aug 8 OIE report on H5N2 in Taiwan
Nigeria, Papua New Guinea take steps to control polio
Nigeria approved a $150 million loan from the World Bank yesterday to support efforts to scale up polio immunization, Reuters reported. Nigeria, along with Afghanistan and Pakistan, is one of the three countries in the world still battling endemic polio transmission.
Nigeria has not recorded a polio case this year, and could be declared polio-free if no new cases are found as of July of 2019.
The 20-year loan required no payments for the first 5 years. Twelve states in Nigeria, including northern states controlled by terrorist organization Boko Haram, are expected to use the bulk of funding for vaccination campaigns.
The goal is to achieve 80% oral vaccine coverage across the country.
In other polio news, the World Health Organization (WHO) said today that nearly 300,000 children were reached during the first of four supplementary polio vaccination campaigns in Papua New Guinea, which recently recorded its first cases of the virus in 18 years. The next round will be held in late August, September, and October, the agency said in a press release.
"I am very pleased that we have been able to protect almost 300,000 children from polio," said Sir Puka Temu, MD, minister for health & HIV/AIDS of Papua New Guinea in a WHO press release. "There was a high turnout in areas where there are significant numbers of mobile populations, which suggests that parents from other provinces brought their children for vaccination."
MERS study shows no sign of infection in Nigerian camel workers
A study today in Eurosurveillance examined serologicl evidence of MERS-CoV infection in people occupationally exposed to infected dromedary camels in a slaughterhouse in Kano, Nigeria, and found that none of the 311 humans tested had any evidence of antibodies to Middle East respiratory syndrome coronavirus (MERS-CoV).
The results are a bit confounding, as camel workers in the Middle East are at an elevated risk of contracting MERS. In addition, camels in this abattoir had been studied several times, and 11% of samples had MERS-CoV RNA in January of 2015. In 2016, when this study was conducted, 0 to 8.4% of camel samples showed RNA. All but 50 of the workers in this study reported direct camel contact, including drinking camel milk and urine, and did not wear personal protective gear.
"This [study's] seropositivity rate is significantly lower than that of the camel abattoir workers in Saudi Arabia (p = 0.0049, Fisher's exact test) and that of the camel barn workers at a race track in Qatar (p = 0.00580)," the authors said.
Instead, this study echoes a Kenyan study, which showed no seroconversion among 760 people with household or occupational exposure to MERS-CoV–seropositive camels.
"MERS-CoV from West Africa, including Nigeria, were genetically and phenotypically distinct from those in East Africa and thus zoonotic potential of viruses from Nigeria may be different from those in Kenya. Overall, these data may suggest that the risk of MERS infection from exposure to infected camels may be lower in some African countries," the authors concluded.
Aug 9 Eurosurveillance study
Saudi Arabia refutes MERS social media rumors
Saudi Arabia’s Ministry of Health (MOH) is refuting rampant social media and press rumors that the country is experiencing an uptick in MERS-CoV cases in Al Ahsa, according to a new post from Avian Flu Diary, an infectious disease tracking blog.
For 3 months, the MOH has not been providing daily updates on MERS, but last week released a PDF document of recent cases.
Though there have been household clusters and transmission from camel contact, the MOH said there is no increase or "outbreak" of Middle East respiratory syndrome-related coronavirus in Al Ahsa, a region in eastern Saudi Arabia.
The Hajj annual pilgrimage is set to begin in 10 days, which usually brings more focus to Saudi Arabia and on the threat of MERS.
Aug 9 Avian Flu Diary post