2016 Angola and DR Congo yellow fever outbreak |
As of 28 October 2016 [1] |
Angola
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DR Congo
( Sylvatic cases are not considered part of the outbreak.) Contents |
Kenya
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China (not on map)
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On 20 January 2016, the health minister of Angola reported 23 cases of yellow fever with 7 deaths among Eritrean and Congolese citizens living in Angola in Viana municipality, a suburb of the capital of Luanda. The first cases (hemorrhagic fever suspected as being yellow fever) were reported in Eritrean visitors beginning on 5 December 2015 and confirmed by the Pasteur WHO reference laboratory in Dakar, Senegal in January. [4] [5] The outbreak was classified as an urban cycle of yellow fever transmission, which can spread rapidly. [6] A preliminary finding that the strain of the yellow fever virus was closely related to a strain identified in a 1971 outbreak in Angola was confirmed in August 2016. [7] Moderators from ProMED-mail stressed the importance of initiating a vaccination campaign immediately to prevent further spread. The CDC classified the outbreak as Watch Level 2 (Practice Enhanced Precautions) on 7 April 2016. [8] The WHO declared it a grade 2 event on its emergency response framework having moderate public health consequences. [9]
At an emergency committee meeting in Geneva, Switzerland on 19 May 2016, the WHO declared that the outbreak was serious and might continue to spread, but decided not to declare a public health emergency of international concern (PHEIC). [10] [11] On 30 May, Margaret Chan, director-general of WHO published a commentary on the bold action needed to prevent further spread of this important communicable disease that caused many historically significant epidemics that took many lives in previous centuries. [12] On 8 June the International Federation of Red Cross and Red Crescent Societies called for a scale-up in the response because of the lack of vaccine and other limitations amid the continuing spread of the outbreak. [13] On 12 August 2016, Daniel R. Lucey, a ProMED mail consultant, wrote an open letter to Dr. Chan requesting that the WHO emergency committee be reconvened to consider a PHEIC because of the continued spread of the disease in Democratic Republic of the Congo, the lack of sufficient vaccine, and concern that it may be spreading into the Republic of the Congo. [14] On 31 August, the decision to not declare a PHEIC was re-confirmed. [15] By 2 September 2016, WHO announced there had been no new cases in either Angola or DR Congo in over a month due to a massive vaccination campaign. [16] On 25 November 2016, WHO announced that four months had passed without a new case. The last case in Angola was on 23 June and the last case in DR Congo was on 12 July. Dr Matshidiso Moeti, WHO Regional Director for Africa, stated: "The current battle against yellow fever in Angola and the Democratic Republic of the Congo is coming to a close, ... But the broader war against the disease is just getting started." [17] ProMED-mail moderator Tom Yuill noted that maintaining vaccination coverage in the two countries will be the next challenge. Approximately 30 million people were vaccinated in the two countries. [18]
By early February, suspected cases were being reported from southern Huila province, about a 1000 kilometers south, and the provinces of Bié, Benguela, Cunene, Cabinda, Hula, Huambo, Malange, Kwanza Sul, Uige, Zaire and Kwanza Norte. [19] As of 9 March 2016, the WHO reported that there were 65 confirmed cases, 813 suspected cases, and 138 deaths in Angola. [20] On 22 March, WHO reported that cases had occurred in 6 of the 18 provinces of Angola, and that transmission was ongoing. Suspected and confirmed cases totaled 1,132, with 375 cases laboratory confirmed and 168 deaths. [21] [22] The situation report of 28 October 2016 reported the most recent number of suspected cases and laboratory-confirmed cases; total deaths and case fatality rates, with suspected and confirmed cases. [23] Local, or autochthonous, transmission had been reported in 12 provinces as of 28 October. Confirmed cases had been reported in 16 of 18 provinces. No new cases were reported during July. [24] The WHO congratulated the Angolan government on its effort to contain the outbreak. [25]
On 22 March 2016, the WHO was notified of 21 deaths from yellow fever in the Democratic Republic of the Congo, some in a province that borders Angola. [26] As of 31 May, 700 suspected cases and 63 deaths had been reported to WHO through the national surveillance system. [27] As of 31 May, 52 cases were laboratory confirmed by the National Institute for Biomedical Research in Kinshasa and the Pasteur Institute in Dakar. Forty-six of the 52 cases were imported from Angola; 2 were classified as autochthonous. Local transmission was still ongoing in urban areas in Angola and DR Congo. WHO classified the outbreak in DR Congo as a Grade 2 Emergency. On 30 May, the GAVI Alliance announced the launch of a mass vaccination campaign in DR Congo, [28] but as of 22 June, vaccine was in short supply. [29] On 20 June, the health minister declared the outbreak of yellow fever in three provinces, including the capital of DR Congo, Kinshasa. [30] Transmission within Kinshasa is of concern because of the large and densely packed population. As of 8 July, WHO was notified of 1798 suspected cases, with 68 confirmed cases (59 imported from Angola) and 85 deaths. [31] In the WHO situation report of 23 September, the last confirmed non-sylvatic or urban case had symptom onset on 12 July. [32]
On 17 March, two cases, including one death, were reported in Kenya, imported from Angola. [33] On 28 March, a rapid response team was deployed into Uganda, where there was ongoing transmission unrelated to the Angola outbreak. [34] According to WHO, cases had been exported from Angola to China, DR Congo, and Kenya, as of 4 May 2016. One case had been reported in Namibia. [35]
ProMED mail reported that as of 3 Aug 2016, 193 cases of yellow fever were suspected in the Republic of the Congo, with 4 cases having tested positive for yellow fever IgM. [36]
On 13 March 2016, the Chinese government confirmed that a 32-year-old male Chinese citizen who had been in Angola had developed yellow fever on return. [37] [38] The case was the first imported yellow fever case in China in history. Yellow fever has never appeared in Asia even though the mosquito vector is present. [39] [40] Additional cases were later reported in people who first had symptoms while in Luanda. [41] ProMED-mail moderator Jack Woodall warned that "spread could make the Ebola and Zika epidemics look like picnics in the park!" and that "international action should start now." [42] Chinese authorities strengthened thermal imaging at airports to detect passengers with elevated body temperatures. [43] A Chinese medical team deployed to Angola vaccinated 120 Chinese nationals as part of epidemic research. [44] More than 250,000 Chinese nationals live in Angola. On 8 April 2016, ten North Korean workers in Angola were reported to have died of yellow fever. [45]
On 25 March 2016, a case was reported in Fujian Province, in a woman who returned from Angola on 12 March. [46] Fujian is within the predicted distribution of Aedes aegypti, the mosquito that transmits the yellow fever virus to humans. Mosquito-borne diseases can become endemic in a new geographic area when local mosquitoes become infected by feeding on an imported case. [47] Between 18 March and 22 April, the WHO was notified of 11 imported cases in China. [48] Officials in Asia were concerned about the threat of yellow fever. [49]
In June 2016, the genetic sequence of a virus from a yellow fever infected Chinese traveler to Angola was posted to GenBank by the Chinese CDC. [50] The strain closely matched a 1971 strain, indicating that the yellow fever virus may have been circulating in the region for at least 45 years. The finding was consistent with earlier phylogenetic analyses performed during the outbreak. [51]
On 28 March, ProMED-mail moderators Jack Woodall and Tom Yuill issued a strongly worded warning on the threat of yellow fever for countries that have endemic dengue fever (and thus the mosquito vector of yellow fever and dengue fever, Aedes aegypti), and particularly for countries in Asia, where until recently yellow fever has never appeared. Urban populations and mosquito-infested slums in Asia and Africa are much larger than in the past. [52] A commentary and accompanying article published in May stressed the potential for spread to Asia by international air travel. [53] [54] Other parts of the world where yellow fever is present but usually in the quiescent jungle cycle, and where there is regular air travel, such as Brazil, may also be vulnerable. [55] They stressed that world stocks of 7 million doses of vaccine have been exhausted in the vaccination campaign against the outbreak in Angola. If yellow fever spread to the 18 countries in Asia where the mosquito vector is present, more than 2 billion people would be at risk. They stated: "Apocalyptic forecasts of the numbers of fatalities from Ebola turned out to be wildly wrong, and we can hope that will again be the case here, but given the way Zika has exploded in the Western hemisphere, we can't count on it." [56] CDC said they could not assist as much in the outbreak because all its experts were involved in efforts against the Zika virus outbreak in the Americas. [57] Starting on 26 April, ProMED-mail issued a series of posts on pre-planning information for countries at risk of importation of yellow fever, covering vaccination, mosquito control, quarantine and personal protection measures. [58] [59]
In an article in JAMA on 9 May 2016, the Georgetown University Law Center called for the WHO to form an emergency committee to determine whether a public health emergency of international concern should be declared. [60] On 12 May, the European Commissioner for Humanitarian Aid and Civil Protection of the European Union announced plans to send a team of the European Medical Corps to Angola on a two-week mission to help control the outbreak and assess the risk of further spread outside Angola. [61] The medical corps was formed after the Ebola outbreak in West Africa that began in 2013, and the mission to Angola was its first deployment. The team included "emergency medical teams, public health and medical coordination experts, mobile biosafety laboratories, medical evacuation planes and logistical support teams". [62] [63]
Efforts to prevent international spread are confounded by the practice of selling falsified yellow fever vaccination certificates. [64] The fake cards are sold to people who are required to have proof of vaccination after travel to areas where yellow fever is endemic. On 11 February 2016, the Pasteur Institute (WHO) in Senegal warned of fake yellow fever vaccine on the international market. [65]
With help from the World Health Organization (WHO), the Angolan Ministry of Health began a campaign of preventive measures including vector control and vaccination in Viana in the first week of February. [66] However, the minister reported that the government had enough vaccine for routine vaccination, but not enough to contain an outbreak. [67] The WHO was supporting the Angolan government in immunization of 6.7 million people in Luanda province with the aim of vaccinating at least 80% of the population at risk of infection. [68] The vaccine supply began to run low by late March, with the director of the CDC, Tom Friedman, warning that "It's possible we could run out of vaccine." [69] The goal of the vaccination campaign in Luanda province was to vaccinate 88 percent of the population (5 804 475 of 6 583 216); ProMED reported that the total national stock of yellow fever vaccine as of 29 Mar 2016 was 1 032 970 doses. [70] As of 10 April 2016, almost 6 million people had been vaccinated in Luanda. [71] On 19 April, the WHO reported that the campaign had been extended into the provinces of Huambo and Benguela where local transmission was reported. [72] On 23 May, the WHO reported that 7.8 million people (91.1%) had been vaccinated in the three provinces. [73] On 23 May, the WHO announced that coverage of an additional 2.7 million people in 5 provinces had reached 55% after 6 days of vaccination. [74]
If the epidemic were to spread, particularly into Asia, the global supply of vaccine would have been insufficient to protect the millions of people that would need to be vaccinated to curb an epidemic. [75] As an emergency measure, experts suggested the dose-sparing strategy to extend existing supplies of vaccine, which the WHO could provide under the Emergency Use Assessment and Listing procedure. [76] The WHO agreed to the recommendation in June 2016, authorizing one-fifth the usual dose during the ongoing outbreak in Angola and DR Congo, but international health regulations still apply to travelers, who must obtain the full dose to quality for the certificate of vaccination. [77]
On June 22, the WHO announced plans to launch a pre-emptive emergency vaccination campaign beginning in July in highly trafficked borders areas of Angola and DR Congo and in densely populated Kinshasa. [78] On 20 July, the DR Congo government launched a campaign to deliver 1 million doses of yellow fever vaccine over 10 days. [79] In August, the WHO with partners including Médecins sans Frontières, International Federation of the Red Cross and UNICEF launched another campaign to vaccinate more than 14 million people in Angola and DR Congo. [80] On 2 September, WHO announced that the campaign to vaccinate the 7.7 million residents of Kinshasa, the capital of DR Congo, had been completed in record time and before the beginning of the rainy season in September when the mosquito population expands. [81] The campaign required 10 million specialized syringes and training of 40,000 vaccinators, using the dose sparing strategy of 1/5 the usual dose. Later studies found that the one-fifth-dose vaccine was just as protective as the full dose, even 10 years after the vaccination. [82]
In August it was reported that of the 6 million vaccine doses shipped by WHO to Angola in February, one million doses went missing, resulting in shortages to fight the spreading epidemic in DR Congo. [83] Vaccine and syringes might have been diverted for sale in private markets. [84]
In the situation report of 23 September, the WHO announced a second phase of the vaccination campaign in Angola and a planned pre-emptive vaccination campaign for the Republic of Congo. [85]
In June 2016, a WHO representative in Luanda said that the initial investigation of the outbreak was thrown off course because the first cases in December 2015—the sick Eritrean visitors—had what were later identified as fake yellow fever vaccination certificates. All had been to the same restaurant, so food poisoning was initially suspected as the cause of the mystery illness. [86] It was more than a month before blood samples from the Eritreans reached the Pasteur Institute lab and yellow fever was recognized. Public health experts identified that as one factor that delayed the response to the outbreak, which came close to being a much larger disaster, if vaccine supplies had not been successfully raised in time, or the disease had spread to other countries and continents. [87] The concurrent Zika outbreak drew attention away from a potentially far more serious epidemic of yellow fever. [88]
Yellow fever is a viral disease of typically short duration. In most cases, symptoms include fever, chills, loss of appetite, nausea, muscle pains—particularly in the back—and headaches. Symptoms typically improve within five days. In about 15% of people, within a day of improving the fever comes back, abdominal pain occurs, and liver damage begins causing yellow skin. If this occurs, the risk of bleeding and kidney problems is increased.
Measles is a highly contagious, vaccine-preventable infectious disease caused by measles virus. Symptoms usually develop 10–12 days after exposure to an infected person and last 7–10 days. Initial symptoms typically include fever, often greater than 40 °C (104 °F), cough, runny nose, and inflamed eyes. Small white spots known as Koplik's spots may form inside the mouth two or three days after the start of symptoms. A red, flat rash which usually starts on the face and then spreads to the rest of the body typically begins three to five days after the start of symptoms. Common complications include diarrhea, middle ear infection (7%), and pneumonia (6%). These occur in part due to measles-induced immunosuppression. Less commonly seizures, blindness, or inflammation of the brain may occur. Other names include morbilli, rubeola, red measles, and English measles. Both rubella, also known as German measles, and roseola are different diseases caused by unrelated viruses.
Polio vaccines are vaccines used to prevent poliomyelitis (polio). Two types are used: an inactivated poliovirus given by injection (IPV) and a weakened poliovirus given by mouth (OPV). The World Health Organization (WHO) recommends all children be fully vaccinated against polio. The two vaccines have eliminated polio from most of the world, and reduced the number of cases reported each year from an estimated 350,000 in 1988 to 33 in 2018.
Mpox is an infectious viral disease that can occur in humans and other animals. Symptoms include a rash that forms blisters and then crusts over, fever, and swollen lymph nodes. The illness is usually mild and most of those infected will recover within a few weeks without treatment. The time from exposure to onset of symptoms ranges from five to twenty-one days and symptoms typically last from two to four weeks. Cases may be severe, especially in children, pregnant women or people with suppressed immune systems.
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Polio eradication, the permanent global cessation of circulation of the poliovirus and hence elimination of the poliomyelitis (polio) it causes, is the aim of a multinational public health effort begun in 1988, led by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF) and the Rotary Foundation. These organizations, along with the U.S. Centers for Disease Control and Prevention (CDC) and The Gates Foundation, have spearheaded the campaign through the Global Polio Eradication Initiative (GPEI). Successful eradication of infectious diseases has been achieved twice before, with smallpox in humans and rinderpest in ruminants.
Program for Monitoring Emerging Diseases is among the largest publicly available emerging diseases and outbreak reporting systems in the world. The purpose of ProMED is to promote communication amongst the international infectious disease community, including scientists, physicians, veterinarians, epidemiologists, public health professionals, and others interested in infectious diseases on a global scale. Founded in 1994, ProMED has pioneered the concept of electronic, Internet-based emerging disease and outbreak detection reporting. In 1999, ProMED became a program of the International Society for Infectious Diseases. As of 2016, ProMED has more than 75,000 subscribers in over 185 countries. With an average of 13 posts per day, ProMED provides users with up-to-date information concerning infectious disease outbreaks on a global scale.
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Dr. Robert Kezaala is a medical doctor, epidemiologist, scholar and public health leader in the field of immunization and health emergencies. Currently he is serving as a Senior Health Advisor and team lead for Accelerated Immunization Initiatives: measles, rubella, epidemic meningitis and yellow fever control and Immunization in Emergencies at the United Nations Children’s Fund.
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