ZIKA VIRUS (02): THAILAND 2023
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Date: Thu 11 Jan 2024
Source: The Telegraph [edited]
https://www.telegraph.co.uk/global-health/science-and-disease/zika-cases-surge-by-almost-300-per-cent-in-thailand/
Zika has surged to levels not seen since before the pandemic in
Thailand, with more than 750 people infected and at least 13 babies
born with birth defects in 2023.
The pathogen has long circulated in the southeast Asian nation, but
cases jumped by almost 300% last year [2023] as the virus, carried by
the Aedes aegypti mosquito, resurfaced following several years of
limited transmission. According to government data, 758 people tested
positive, including 33 pregnant women, compared to just 190 in 2022
and 63 in 2021.
While Zika is generally mild — symptoms include a rash, fever, and
joint pain, though many cases are asymptomatic — it is dangerous if
contracted during pregnancy.
As well as being linked to miscarriages and premature births, it can
cause congenital malformations in newborns, including microcephaly,
which can cause deformity and brain damage, as well as limb
contractures, eye abnormalities, and hearing loss.
In Thailand, 13 babies were born with these health issues last year
[2023].
“For pregnant women, preventive measures against insect-transmitted
diseases have been recommended, such as avoiding mosquito-prone areas,
wearing long-sleeved clothing, using insect repellents following
global health organisation guidelines,” said Prof Yong Poovorawan,
head of the Center of Excellence in Clinical Virology at Chulalongkorn
University in Bangkok.
He added that there is a risk to tourists: a 33-year-old woman tested
positive in the Netherlands after a trip to Thailand in December
[2023], while 2 patients were hospitalised with acute infections in
Germany after a 3-week holiday in November [2023].
“However, in comparison to the total number of tourists visiting
Thailand … it’s not surprising to have had cases of tourists
contracting diseases like Zika. This pattern aligns with the situation
among the Thai population,” Prof Poovorawan said.
The jump in Zika comes as dengue — which is also spread by the Aedes
aegypti mosquito — erupted across the globe, with major outbreaks in
countries as diverse as Peru, Burkina Faso, Bangladesh, and Thailand.
“Diseases transmitted by insects … tend to have cycles of outbreaks
where there might be a surge in cases followed by periods of relative
calm, lasting anywhere from 1-3 years,” Prof Poovorawan told the
Telegraph.
“Similar to this pattern, Zika virus cases have increased this year,
paralleling the rise in dengue fever cases,” he said, adding that it
is the highest Zika count in Thailand since 2016.
“It’s challenging to predict whether [2024] will experience a severe
outbreak or not.”
Zika has long been a threat, with sporadic outbreaks since the 1960s,
but it was in 2016 that concerns peaked.
The World Health Organization declared a global health emergency when
at least 1.5 million people contracted Zika in an unprecedented
outbreak in South America; the virus was then linked to microcephaly
in nearly 4000 babies in Brazil.
Transmission has gradually subsided not only in the region — the
Americas reported 3000 cases in 2023, mostly from Brazil, Bolivia,
Guatemala, Belize, and Colombia — but also worldwide.
Yet the disease remains a threat across Africa, the Americas, Asia,
and the Pacific; in total, 89 countries have detected cases, though
patchy surveillance makes it difficult to assess the situation in much
of the world.
Thailand is one of the countries that best tracks the virus as it is
incorporated into the nation’s routine surveillance system, according
to a spokesperson from the WHO’s country office.
The spokesperson added that, with immunity against Zika waning almost
a decade after the last major outbreak, the world should be on alert,
especially as parallel outbreaks of different arboviruses (a family
that includes Zika and dengue) are “common.”
“Zika emergence was 8 years ago, which is enough time to accumulate
susceptible persons and fuel a new epidemic,” they said.