This is the first arbovirus surveillance update of the year, and we have already detected West Nile virus (WNV) activity. Of the 743 pooled mosquito samples tested so far, 3 have tested positive. These were collected in Franklin, Lorain and Summit Counties. This is similar in timing to our first positive samples last year, but we’re also seeing reports of WNV activity in neighboring states that includes an equine case in Kentucky and 2 human cases in Indiana. It is still too early in the surveillance season to predict whether or not this will be a worse than normal year. However, these reports serve as a reminder that WNV infected mosquitoes are active and now is the time to increase your community and public education efforts to include these points:
In the Florida Keys on Election Day, along with the presidential race, one of the most controversial items on the ballot dealt with Zika. In a nonbinding vote countywide, residents in the Florida Keys approved a measure allowing a British company to begin a trial release of genetically modified mosquitoes. Armed with that approval, local officials voted Saturday to try out what they hope will be a new tool in the fight against Zika.
Speakers included Dr. Stephen Higgs from Kansas State University, Dr. Brian Foy from Colorado State University, Dr. Constancia Ayres from Fiocruz in Brazil, Dr. Anthony James from the University of California, Irvine, and Dr. Fiona Hunter from Brock University, all of whom appear in the video below:
Source credit: The Ohio Department of Agriculture, 9/16/2016
(REYNOLDSBURG, OH) – The first positive case of West Nile Virus (WNV) in an Ohio horse has been confirmed in 2016.
Testing on samples taken from a seven-year-old Standardbred in Tuscarawas County confirmed the positive WNV diagnosis to the Ohio Department of Agriculture Sept. 12. The horse’s veterinarian first examined the animal Aug. 29. The animal was euthanized after exhibiting significant clinical signs, including shaking, agitation and thrashing. The horse had not been vaccinated.
West Nile Virus is transmitted to horses via bites from infected mosquitoes. Clinical signs for WNV include flulike symptoms, where the horse seems mildly anorexic and depressed. Changes in mentality, drowsiness, driving or pushing forward (often without control) and asymmetrical weakness may be observed. Mortality rate from WNV can be as high as 30-40 percent in horses. Infection with WNV does not always lead to signs of illness in people or animals. WNV is endemic in the United States and Ohio has reported three positive cases in horses each of the last few years.
“This incident in Tuscarawas County should serve as an alert to all horse owners to vaccinate their animals against West Nile Virus,” said State Veterinarian Dr. Tony Forshey. “Vaccines are a proven and effective prevention tool and I encourage all owners to talk to their local vet for options and advice on how to keep their animals healthy.”
In addition to vaccinations, horse owners also should work to reduce the mosquito population and eliminate possible breeding areas. Recommendations include: removing stagnant water sources; keeping animals inside during the bugs’ feeding times, which are typically early in the morning and evening; and using mosquito repellents.
Researchers have identified the Zika virus in mosquito species other thanAedes aegypti, which is largely responsible for the current outbreaks of Zika infection, raising concerns that other mosquitoes may be capable of transmitting the virus. However, a new study demonstrates that mosquitoes in the genus Culex are highly unlikely to transmit the infection to humans in the United States. The study was published inVector-Borne and Zoonotic Diseases.
The report demonstrates that the most widespread and abundant Culexspecies in the United States are very resistant to Zika virus infection, even when exposed to high levels of the virus in bloodmeals. The study showed that the southern house mosquito (Culex quinquefasciatus), for example, is refractory to infection with Zika virus. This finding has important implications for Florida and other emerging areas of Zika virus infection, and the authors recommend that mosquito-control efforts in areas of Florida with non-travel-related cases of infection should continue to focus on Aedes species.
According to University of Aix-Marseille visiting Professor Ernest Gould, who was not involved in the study, “[This paper] describes laboratory experiments to assess the transmission competence of Culex species and provides strong evidence to support the view that Culex species mosquitoes are highly unlikely to be important vectors of Zika virus. This report provides very helpful guidance for health agencies charged with the responsibility of controlling local mosquito populations in regions of North America where Zika virus presents a potential threat.”
However, an unpublished study from Brazil has shown that BrazilianCulex quinquefasciatus can be infected with Zika virus, and that Culex quinquefasciatus has been found in the city of Recife, where Zika is known to occur.
On Sunday morning, the South Carolina honey bees began to die in massive numbers.
Death came suddenly to Dorchester County, S.C. Stressed insects tried to flee their nests, only to surrender in little clumps at hive entrances. The dead worker bees littering the farms suggested that colony collapse disorder was not the culprit — in that odd phenomenon, workers vanish as though raptured, leaving a living queen and young bees behind.
Instead, the dead heaps signaled the killer was less mysterious, but no less devastating. The pattern matched acute pesticide poisoning. By one estimate, at a single apiary — Flowertown Bee Farm and Supply, in Summerville — 46 hives died on the spot, totaling about 2.5 million bees.