First West Nile Virus case recorded; BAMP cautions Bajans

A single case of the potentially deadly mosquito-borne West Nile Virus (WNV) was recorded here last month, the World Health Organisation (WHO) has revealed, prompting the Barbados Association of Medical Practitioners (BAMP) to warn people not to mistake the illness for dengue fever whose symptoms are similar.

BAMP president Dr Lynda Williams responded on Friday to the news revealed by the WHO of the island’s first confirmed human infection – in “a child less than 15 years old residing in Bagatelle, St Thomas” in mid-September.

The Ministry of Health had not communicated the discovery to the Barbadian public, but the WHO disclosed on Thursday that the ministry, the International Health Regulations National Focal Point, had notified of the case last month, after receiving the test results on the child who took ill in June.

The child began experiencing symptoms on June 10, including headache, fever, vomiting, neck pain, and knee pain, the WHO reported. A dengue fever test on June 14 was negative. The patient was admitted to paediatric intensive care on June 16 with “worsening of signs and symptoms, including joint pain, abdominal pain, altered mental status, and slurred speech”.

Cerebrospinal fluid tests ruled out some bacterial and viral pathogens, but the child’s condition worsened, the WHO said. Blood samples sent to the Mayo Clinic on September 3 confirmed WNV antibodies (IgG) on September 14.

“The patient remains under care and is recovering,” WHO said.

West Nile virus is generally carried by migratory birds and transmitted by mosquitoes to humans, horses, and other mammals.

“This is the first human case of WNV infection detected in Barbados. Additionally, no infections have been previously documented in birds or horses in this country, making this case both unusual and unexpected,” it said.

According to the WHO, the patient reportedly visited a horse stable in February and “a beach frequented by horses” on June 8, two days before the onset of symptoms.

It said: “Although these exposures to horses were considered risk factors for WNV infection, the precise source of infection remains unspecified. No other suspected cases of [West Nile] were identified, but public health authorities continue to monitor the situation closely.”

Symptoms of WNV include fever, headache, body aches, vomiting, diarrhea, or rash. The virus is primarily transmitted through mosquito bites, with birds as the natural hosts, and there is no evidence to suggest that the virus spreads easily between humans or from horses to mosquitoes. There are no vaccines to prevent or medicines to treat West Nile in people.

Urging vigilance, BAMP’s Dr Williams told Barbados TODAY: “I just want people to realise it is no more dangerous than dengue. In the same way, we must not assume that everything is dengue. That’s the point I want to get across. We must not assume that everything that looks like dengue is dengue, and doctors need to be made aware, and look out for the possibility that some things that seem to be dengue may not be.”

She explained that there are several other viruses circulating, besides WNV, with similar symptoms.

“Try hard to prevent mosquito bites,” the general practitioner advised. “It has the same sort of risk potential as other mosquito-borne illnesses. The difference, I think, with this one is because of the neurological complications, such as encephalitis and paralysis, there is a lot more concern. But the reality is that very, very, very few people who get West Nile Virus will end up with neurological complications.

“The actual numbers are that between 20 and 40 per cent will develop any symptoms, and less than one per cent will develop neurological complications. Although the potential exists, you just have to be aware that it is out there and be able to find out what is causing a person to have these dengue-like symptoms.”

The BAMP leader noted that many people who get dengue-like symptoms stay home and treat the illness themselves, rather than seek medical care.

“So that is why I am trying to get the word across: if you are really ill, have a high fever, muscle pain, and joint pain, don’t assume it is dengue. Go and get tested and confirm what has happened,” Dr Williams advised.

The WHO said that while WNV has spread in the Caribbean before,  likely via infected migratory birds, no cases have been documented in birds or horses in Barbados.

However, it added, “It is possible that the virus is circulating in birds and horses undetected”.

“Despite this, the overall impact on public health remains limited at this stage, as there is currently only one recorded human case and appropriate public health response measures have been implemented. WHO considers the current risk from WNV as low but will continue to evaluate the epidemiological situation in Barbados.”

After confirmation of the single case, the WHO said, health authorities here conducted interviews with the patient’s parents to investigate risk factors such as exposure to animals known to carry WNV, recent travel history, and other relevant factors; and implemented ongoing epidemiological surveillance and testing to ensure no further cases are missed and to evaluate the potential risk of local transmission in the area.

emmanueljoseph@barbadostoday.bb