WHO sees ‘high risk’ of polio virus spreading across Gaza, assessment underway
- July 25, 2024
- Posted by: OptimizeIAS Team
- Category: DPN Topics
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WHO sees ‘high risk’ of polio virus spreading across Gaza, assessment underway
Subject: Science and tech
Sec: Health
Context:
Circulating vaccine-derived poliovirus type 2 had been isolated from environmental samples from sewage, in war-ravaged Gaza.
More about News:
- There is a high risk of spreading of the circulating vaccine-derived polio virus in Gaza, not only because of the detection but because of the very dire situation with the water sanitation.
- Poliomyelitis, which is spread mainly through the fecal-oral route, is a highly infectious virus that can invade the nervous system and cause paralysis. It mainly affects children under the age of 5.
- Without proper health services, the population of Gaza is particularly vulnerable to outbreaks of disease.
Circulating vaccine-derived polio virus:
Wild poliovirus (WPV) is the most commonly known form of the poliovirus. However, there is another form of polio that can spread within communities: circulating vaccine-derived poliovirus, or cVDPV.
- Transmitted from :
- Person-to-person
- Mainly through the fecal-oral route or, less frequently
- By contaminated water or food
- The virus multiplies in the intestine, from where it can invade the nervous system and cause paralysis.
Incubation period : Usually 7-10 days but can range from 4-35 days.
- Up to 90% of those infected are either asymptomatic or experience mild symptoms and the disease usually goes unrecognized.
- Vaccine-derived poliovirus is a well-documented strain of poliovirus mutated from the strain originally contained in OPV.
- OPV contains a live, weakened form of poliovirus that replicates in the intestine for a limited period, thereby developing immunity by building up antibodies.
- On rare occasions, when replicating in the gastrointestinal tract, OPV strains can genetically change and may spread in communities that are not fully vaccinated against polio, especially in areas where there is poor hygiene, poor sanitation, or overcrowding.
- The lower the population’s immunity, the longer vaccine-derived poliovirus survives and the more genetic changes it undergoes.
- The vaccine-derived virus can genetically change into a form that can cause paralysis as does the wild poliovirus – this is what is known as a vaccine-derived poliovirus (VDPV).
To comply with the Temporary Recommendations issued under the PHEIC, any country that have had an importation of cVDPV2 with local transmission should
- Declare the outbreak as a national public health emergency.
- Encourage residents and long-term visitors to receive a dose of IPV four weeks to 12 months prior to international travel.
- Ensure that travellers who receive such vaccination have access to an appropriate document to record their polio vaccination status.
- Further intensify efforts to increase IPV immunization coverage, including sharing coverage data.
- Intensify regional cooperation and cross border coordination to enhance surveillance for prompt detection of poliovirus, and vaccinate refugees, travellers and cross border populations, according to the advice of the Advisory Group.