Zika virus: Should Nigeria worry? | Nigeria Newspaper - Latest Nigeria News paper

1.2.16

Zika virus: Should Nigeria worry?

By
Against the background that Nigeria had once diagnosed patients with the Zika virus, now that it has resurfaced and is spreading rapidly, from Latin America, reaching into the United States of America and Canada, with estimated cases expected from Africa, KEHINDE OYETIMI examines the intricacies surrounding the disease, which spreads through mosquito bites,
Nigeria’s preparedness, and the concerns raised, especially regarding mosquito-prone areas such as Nigeria.
When results of a scientific research, titled “Zika virus infections in Nigeria: Virological and seroepidemiological investigations in Oyo State” written by A.H. Fagbami, and undertaken at the Virus Research Laboratory, University of Ibadan, Ibadan, Nigeria, was published in the Journal of Hygiene in 1979, not so much was thought of it by the Nigerian government at the time, especially as the research indicated that the virus was unlikely to become a pandemic.
According to the results of the research, “Two Zika virus isolations were made from 10778 heparinized blood specimens collected between 1971 and 1975. One was obtained in July 1971 from the blood of a male child aged 21/2 years. The second was made in May 1975 from the serum of a 10-year-old boy in Igbo-Ora (Fagbami, 1977). The two virus isolations were obtained in early and peak rainy seasons - the first patient had mild nondescript febrile illness and no other clinical details were obtainable. The second patient reported with fever, headache and body pains.
“The present survey showed that Zika virus immunity is prevalent among Nigerians; 40 per cent of persons tested had neutralizing antibodies. Since 50 per cent of Zika-immune individuals tested had monotypic Zika N antibody or antibodies to Zika and one other flavivirus, the immunity reported in this study cannot be attributed to immunological cross reaction within the flavivirus serogroup. Sera containing monotypic antibodies were found more frequently among the younger age groups. Persons in this group are less likely to have multiple flavivirus infections, which are often responsible for broad heterologous cross reactions.
The results of the haemagglutination inhibition test showed that HI antibodies to Zika and related viruses were prevalent among Nigerians, 69 per cent of persons tested were positive. It has been shown that neutralizing antibodies develop earlier than HI antibodies (Southam, 1956). The detection of Zika neutralizing antibody in sera of persons negative for flavivirus HI antibody suggested that such persons probably had had recent Zika virus infection.
Apart from the serological evidence of Zika virus activity in Nigeria, previous (Moore et al. 1975) and the present virus isolations from human blood further confirmed the active transmission of this virus infection in the country. Although only a few isolates were obtained in past and present studies, the demonstration of a high rate of immunity to the virus in all the areas studied and elsewhere (Boorman & Draper, 1968; Macnamara et al. 1959) suggested that Zika virus infection is more widely spread. The low isolation rate may be attributed to the fact that infected persons often present with mild, nondescript illness and it is conceivable that such cases may not report to hospital clinics. Clinically Zika virus infection is manifested by fever, headache, body pains and rash (Simpson, 1964; Moore et al. 1975).
In the present investigations, similar manifestations were observed in the two patients from whom the virus was isolated. In Nigeria and many other developing countries, malaria is the common cause of febrile illness (Downs, 1975). The similarities in the clinical presentation of malaria and many arthropod-borne viral infections often result in misdiagnosis especially in places where laboratory facilities are lacking. Although clinical Zika virus infection is mild, the high prevalence of immunity in Nigeria has some epidemilogical significance. It was shown by Fabiyi & Macnamara (1962) that better antibody response was found in persons without preimmunization flavivirus antibody following yellow fever vaccination. The high percentage of persons immune to Zika virus and other flaviviruses may influence the outcome of a yellow fever immunization programme. It was also shown by Henderson et al. (1970) that such immunity to heterologous flaviviruses might even modify the course of yellow fever infection. Yellow fever is known to be endemic in Nigeria; severe epidemics have been reported in several parts of the country (Carey et al. 1972; Monath et al. 1973; Fagbami et al. 1976). However, there had not been any documented outbreak of this disease in the areas studied. The high prevalence of antibody to Zika and other related viruses might contribute to the absence of yellow fever in these areas. Zika virus has been isolated from Aedes africanu89 (Dick et al. 1952; Weinbren & Williams, 1958). In Nigeria the isolates were obtained from A. luteocephalus (Lee, 1969). This mosquito is a forest Aedes species; however, the immunity to Zika virus has been demonstrated in all the urban communities studied. It is probable that other species of mosquitoes, possibly A. aegypti, play an important role in the transmission of the virus in Nigeria.”
Fast forward over 35 years later, the world is currently on red alert regarding the same Zika virus, which, is largely regarded as a danger zone for pregnant women.
With the spread of the disease across the borders of Latin America, with countries such as the United States and Canada declaring patients infected with the disease, it becomes necessary to wonder, if Nigeria shouldn’t as well step up its efforts towards ensuring that the disease doesn’t constitute another major scare, as it did with the recent case of Ebola virus, especially considering the fact that Nigeria already has a history with the same Zika virus.

Victim recounts experience
According to ABC News, “there are currently 36 people in the U.S. who have been diagnosed with the Zika virus, including four pregnant women – two in Illinois and one each in Washington DC and New York. Those infected are spread across 11 states and Washington, D.C., according to the U.S. Centers for Disease Control and Prevention. All of those infected contracted the virus outside of the U.S. before returning, according to health officials.”
Lizzie Morales told ABC’s Houston station KTRK-TV her experience with Zika virus.
“You have no strength or energy to sit down. You just want to lay down and sleep. Christmas Eve, I was scratching my chest. I had bumps on my lips, eyes, ears,” she said.
According to Professor of Biology at Georgetown University, Dr Peter Armbruster, and published by ABC News, “It is very likely an infected traveler from French Polynesia that traveled to Brazil was likely the source of the Brazilian invasion. Whether it is someone associated with the [World Cup], we do not know for sure.”

Women urged to stay off pregnancy till 2018
An outbreak of the disease in Brazil led to an alert by the Pan American Health Organization (PAHO) in May 2015. The U.S. Centre for Disease Control and Prevention has issued a travel alert for 24 countries and territories where the virus transmission is ongoing. Those countries and territories are: Brazil, Colombia, El Salvador, French Guiana, Guatemala, Haiti, Honduras, Martinique, Mexico, Panama, Paraguay, Suriname, Venezuela, Puerto Rico, U.S. Virgin Islands, Dominican Republic, Barbados, Bolivia, Ecuador, Guadeloupe, Saint Martin, Guyana, Cape Verde and Samoa.
Also, reports by Al Jazeera stated that El Salvador’s vice-minister of public health, Eduardo Espinoza, last week, told women who were already pregnant to stay covered outdoors to reduce the risk of mosquito bites.
“We’d like to suggest to all the women of fertile age that they take steps to plan their pregnancies, and avoid getting pregnant between this year and next,” he said.

There is no need to panic –FG
As part of efforts to ensure that the disease doesn’t miraculously resurrect upon Nigerian shores, especially for a country that is still working assiduously towards “rolling back” malaria, also spread through mosquitoes, the Federal Government over the weekend, issued an alert about the outbreak of Zika virus disease and subsequently directed that Nigerians, especially pregnant women, be restricted from travelling to Latin America for now until the situation improves.
According to the directive which called on the Nigeria Center for Disease Control (NCDC) to include Zika virus diagnosis as part of ongoing efforts to manage the Lassa fever outbreak in the country, said anyone coming from any of the Latin American countries undergo interrogation at the various ports of entry to rule out possible carriers of the virus and ensure that the situation can be kept in check.
According to a statement by the Director of Press and Public Relations in the Federal Ministry of Health, Mrs. Boade Akinola, the Minister of Health, Professor Isaac Adewole, was quoted as saying that “there is no single case of Zika virus infection in the country and there is no need to panic,” just as he noted that the Federal Ministry of Health would continue to monitor the situation and update Nigerians on further developments.
“The World Health Organisation (WHO) has raised a global alert because the disease has affected about 23 countries in Americas especially in Latin America. At the moment, there is no cure or vaccine for Zika virus infection.
“The Federal Ministry of Health hereby advises a travel restriction especially by pregnant women to Latin America for now until situation improves. In addition, we have directed the NCDC to include Zika virus diagnosis as part of ongoing effort to manage Lassa fever outbreak in the country,” Adewole stated.
Continuing, the Federal Minister for Health stated that “Nigerians should be vigilant and report promptly any case of unexplained fever that lasts more than 48 hours, especially in those that travelled to Latin America recently, to health care professionals. Nigerians working at various ports of entry into the country should interview anyone coming from any of the Latin American countries for evidence Zika virus symptoms.”

Virus known to circulate in Africa –WHO
While reports of the disease’s findings had begun to creep stealthily into media reports as at May 2015, when the first infection was reported, with recent findings, according to the WHO, there has been an increase in infected persons, especially in Brazil, as health authorities reported an increase in Zika virus infections as well as an increase in babies born with microcephaly in northeast Brazil, with investigations revealing that there may just be a link between both, although other potential causes are still being investigated.
According to the WHO fact sheet, as published on the organisation’s website, “Zika virus disease is caused by a virus transmitted by Aedes mosquitoes. People with Zika virus disease usually have a mild fever, skin rash (exanthema) and conjunctivitis. These symptoms normally last for two to seven days. There is no specific treatment or vaccine currently available. The best form of prevention is protection against mosquito bites. The virus is known to circulate in Africa, the Americas, Asia and the Pacific.”

The Zika virus, according to the WHO report, was “first identified in Uganda in 1947 in rhesus monkeys through a monitoring network of sylvatic yellow fever. It was subsequently identified in humans in 1952 in Uganda and the United Republic of Tanzania. Outbreaks of Zika virus disease have been recorded in Africa, the Americas, Asia and the Pacific. During large outbreaks in French Polynesia and Brazil in 2013 and 2015 respectively, national health authorities reported potential neurological and auto-immune complications of Zika virus disease.
“Zika virus is transmitted to people through the bite of an infected mosquito from the Aedes genus, mainly Aedes aegypti in tropical regions. This is the same mosquito that transmits dengue, chikungunya and yellow fever. Zika virus disease outbreaks were reported for the first time from the Pacific in 2007 and 2013 (Yap and French Polynesia, respectively), and in 2015 from the Americas (Brazil and Colombia) and Africa (Cape Verde). In addition, more than 13 countries in the Americas have reported sporadic Zika virus infections indicating rapid geographic expansion of Zika virus.”

Diagnosis, symptoms, and prevention
According to WHO, “Zika virus is diagnosed through PCR (polymerase chain reaction) and virus isolation from blood samples. Diagnosis by serology can be difficult as the virus can cross-react with other flaviviruses such as dengue, West Nile and yellow fever.
While there is no readily available vaccine to prevent the disease, preventive and control measures recommended by the WHO are, “relies on reducing mosquitoes through source reduction (removal and modification of breeding sites) and reducing contact between mosquitoes and people. This can be done by using insect repellent; wearing clothes (preferably light-coloured) that cover as much of the body as possible; using physical barriers such as screens, closed doors and windows; and sleeping under mosquito nets. It is also important to empty, clean or cover containers that can hold water such as buckets, flower pots or tyres, so that places where mosquitoes can breed are removed.”
The WHO also calls for special attention and help for those who may not be able to provide adequate care for themselves in preventing the disease such as children, the sick or the elderly. In case of an outbreak, the WHO advises that spraying of insecticides be carried out. Evaluation Scheme may also be used as larvicides to treat relatively large water containers. Travellers are also encouraged to take basic precautions to protect themselves from mosquito bites.

Treatment and further action
According to various health organisations and research scientists, Zika virus disease usually presents minor symptoms and as such requires no specific treatment and plenty of rest, consumption of more fluids, as well as recommended treatment for pain and fever can be adopted. However, in the event that the symptoms become worse, patients are advised to seek further medical care.
The WHO is supporting countries to control Zika virus disease through defining and prioritising research into Zika virus disease by convening experts and partners; enhancing surveillance of Zika virus and potential complications; strengthening capacity in risk communication to help countries meet their commitments under the International Health Regulations; provision of training on clinical management, diagnosis and vector control including through a number of WHO Collaborating Centres; strengthening the capacity of laboratories to detect the virus; providing support for health authorities to implement vector control strategies aimed at reducing Aedes mosquito populations such as providing larvicide to treat standing water sites that cannot be treated in other ways, such as cleaning, emptying, and covering them; preparing recommendations for clinical care and follow-up of people with Zika virus, in collaboration with experts and other health agencies.
Government at all levels, stakeholders in all sectors of the economy, as well as Nigerians in general have their work cut out towards preventing the future generation, seeing as the disease has especially heavy consequences on pregnant women. It would be almost impossible to cut off all connections with foreign countries, especially in the face of major business investments currently being secured by the President Muhammadu Buhari-led administration, collaboration with nations to fight corruption as well as foreign aid in the efforts to successfully wipe out insurgency.
Also, major sporting events as well also brings nations together, and with Nigeria’s improving performance, however minute, on a global scale, it is therefore necessary for all hands to be on deck to ensure that the disease doesn’t become another damning migraine for a nation that has enough battles with terrorists, militants, rats, mosquitoes, among other negative distractions.

0 comments:

Post a Comment

Latest News

Popular News