The global outbreak alert and response network.

The Global Outbreak Alert and Response Network (GOARN) was established in 2000 as a network of technical institutions, research institutes, universities, international health organisations and technical networks willing to contribute and participate in internationally coordinated responses to infectious disease outbreaks. It reflected a recognition of the need to strengthen and coordinate rapid mobilisation of experts in responding to international outbreaks and to overcome the sometimes chaotic and fragmented operations characterising previous responses. The network partners agreed that the World Health Organization would coordinate the network and provide a secretariat, which would also function as the operational support team. The network has evolved to comprise 153 institutions/technical partners and 37 additional networks, the latter encompassing a further 355 members and has been directly involved in 137 missions to 79 countries, territories or areas. Future challenges will include supporting countries to achieve the capacity to detect and respond to outbreaks of international concern, as required by the International Health Regulations (2005). GOARN's increasing regional focus and expanding geographic composition will be central to meeting these challenges. The paper summarises some of network's achievements over the past 13 years and presents some of the future challenges.

Laboratory diagnosis of Ebola hemorrhagic fever during an outbreak in Yambio, Sudan, 2004.

Between the months of April and June 2004, an Ebola hemorrhagic fever (EHF) outbreak was reported in Yambio county, southern Sudan. Blood samples were collected from a total of 36 patients with suspected EHF and were tested by enzyme-linked immunosorbent assay (ELISA) for immunoglobulin G and M antibodies, antigen ELISA, and reverse-transcription polymerase chain reaction (PCR) of a segment of the Ebolavirus (EBOV) polymerase gene. A total of 13 patients were confirmed to be infected with EBOV. In addition, 4 fatal cases were classified as probable cases, because no samples were collected. Another 12 patients were confirmed to have acute measles infection during the same period that EBOV was circulating. Genetic analysis of PCR-positive samples indicated that the virus was similar to but distinct from Sudan EBOV Maleo 1979. In response, case management, social mobilization, and follow-up of contacts were set up as means of surveillance. The outbreak was declared to be over on 7 August 2004.

Marburg hemorrhagic fever associated with multiple genetic lineages of virus.

BACKGROUND: An outbreak of Marburg hemorrhagic fever was first observed in a gold-mining village in northeastern Democratic Republic of the Congo in October 1998. METHODS: We investigated the outbreak of Marburg hemorrhagic fever most intensively in May and October 1999. Sporadic cases and short chains of human-to-human transmission continued to occur until September 2000. Suspected cases were identified on the basis of a case definition; cases were confirmed by the detection of virus antigen and nucleic acid in blood, cell culture, antibody responses, and immunohistochemical analysis. RESULTS: A total of 154 cases (48 laboratory-confirmed and 106 suspected) were identified (case fatality rate, 83 percent); 52 percent of cases were in young male miners. Only 27 percent of these men reported having had contact with other affected persons, whereas 67 percent of patients who were not miners reported such contact (P<0.001). Most of the affected miners (94 percent) worked in an underground mine. Cessation of the outbreak coincided with flooding of the mine. Epidemiologic evidence of multiple introductions of infection into the population was substantiated by the detection of at least nine genetically distinct lineages of virus in circulation during the outbreak. CONCLUSIONS: Marburg hemorrhagic fever can have a very high case fatality rate. Since multiple genetic variants of virus were identified, ongoing introduction of virus into the population helped perpetuate this outbreak. The findings imply that reservoir hosts of Marburg virus inhabit caves, mines, or similar habitats.

Mortality among displaced former UNITA members and their families in Angola: a retrospective cluster survey.

OBJECTIVE: To measure retrospectively mortality among a previously inaccessible population of former UNITA members and their families displaced within Angola, before and after their arrival in resettlement camps after ceasefire of 4 April 2002. DESIGN: Three stage cluster sampling for interviews. Recall period for mortality assessment was from 21 June 2001 to 15-31 August 2002. SETTING: Eleven resettlement camps over four provinces of Angola (Bié, Cuando Cubango, Huila, and Malange) housing 149 000 former UNITA members and their families. PARTICIPANTS: 900 consenting family heads of households, or most senior household members, corresponding to an intended sample size of 4500 individuals. MAIN OUTCOME MEASURES: Crude mortality and proportional mortality, overall and by period (monthly, and before and after arrival in camps). RESULTS: Final sample included 6599 people. The 390 deaths reported during the recall period corresponded to an average crude mortality of 1.5/10 000/day (95% confidence interval 1.3 to 1.8), and, among children under 5 years old, to 4.1/10 000/day (3.3 to 5.2). Monthly crude mortality rose gradually to a peak in March 2002 and remained above emergency thresholds thereafter. Malnutrition was the leading cause of death (34%), followed by fever or malaria (24%) and war or violence (18%). Most war victims and people who had disappeared were women and children. CONCLUSIONS: This population of displaced Angolans experienced global and child mortality greatly in excess of normal levels, both before and after the 2002 ceasefire. Malnutrition deaths reflect the extent of the food crisis affecting this population. Timely humanitarian assistance must be made available to all populations in such conflicts.

Risk factors for Marburg hemorrhagic fever, Democratic Republic of the Congo.

We conducted two antibody surveys to assess risk factors for Marburg hemorrhagic fever in an area of confirmed Marburg virus transmission in the Democratic Republic of the Congo. Questionnaires were administered and serum samples tested for Marburg-specific antibodies by enzyme-linked immunosorbent assay. Fifteen (2%) of 912 participants in a general village cross-sectional antibody survey were positive for Marburg immunoglobulin G antibody. Thirteen (87%) of these 15 were men who worked in the local gold mines. Working as a miner (odds ratio [OR] 13.9, 95% confidence interval [CI] 3.1 to 62.1) and receiving injections (OR 7.4, 95% CI 1.6 to 33.2) were associated with a positive antibody result. All 103 participants in a targeted antibody survey of healthcare workers were antibody negative. Primary transmission of Marburg virus to humans likely occurred via exposure to a still unidentified reservoir in the local mines. Secondary transmission appears to be less common with Marburg virus than with Ebola virus, the other known filovirus.

An outbreak of Rift Valley fever in Northeastern Kenya, 1997-98.

In December 1997, 170 hemorrhagic fever-associated deaths were reported in Garissa District, Kenya. Laboratory testing identified evidence of acute Rift Valley fever virus (RVFV). Of the 171 persons enrolled in a cross-sectional study, 31(18%) were anti-RVFV immunoglobulin (Ig) M positive. An age-adjusted IgM antibody prevalence of 14% was estimated for the district. We estimate approximately 27,500 infections occurred in Garissa District, making this the largest recorded outbreak of RVFV in East Africa. In multivariable analysis, contact with sheep body fluids and sheltering livestock in one s home were significantly associated with infection. Direct contact with animals, particularly contact with sheep body fluids, was the most important modifiable risk factor for RVFV infection. Public education during epizootics may reduce human illness and deaths associated with future outbreaks.

An outbreak of Salmonella enteritidis food poisoning in a psychiatric hospital in Dublin, Ireland.

On 29 August 1996 Ireland's Eastern Health Board (EHB) was informed of an outbreak of gastrointestinal illness in a psychiatric hospital in Dublin. Fifty people among 240 members of staff and 183 patients had reportedly fallen ill since 27 August and new