Change search
ReferencesLink to record
Permanent link

Direct link
The 2007 rift valley Fever outbreak in Sudan
Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Infectious Diseases. Federal Ministry of Health, Khartoum, Sudan. (Ahlm o Evander: Rift Valley)
Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Infectious Diseases. (Clas Ahlm)
Umeå University, Faculty of Medicine, Department of Clinical Microbiology, Virology. (Magnus Evander)
2011 (English)In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 5, no 9, e1229Article, review/survey (Refereed) Published
Abstract [en]

Rift Valley fever (RVF) is a neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health and economy. RVF is caused by RVF virus (RVFV) affecting humans and a wide range of animals. The virus is transmitted through bites from mosquitoes and exposure to viremic blood, body fluids, or tissues of infected animals. During 2007 a large RVF outbreak occurred in Sudan with a total of 747 confirmed human cases including 230 deaths (case fatality 30.8%); although it has been estimated 75,000 were infected. It was most severe in White Nile, El Gezira, and Sennar states near to the White Nile and the Blue Nile Rivers. Notably, RVF was not demonstrated in livestock until after the human cases appeared and unfortunately, there are no records or reports of the number of affected animals or deaths. Ideally, animals should serve as sentinels to prevent loss of human life, but the situation here was reversed. Animal contact seemed to be the most dominant risk factor followed by animal products and mosquito bites. The Sudan outbreak followed an unusually heavy rainfall in the country with severe flooding and previous studies on RVF in Sudan suggest that RVFV is endemic in parts of Sudan. An RVF outbreak results in human disease, but also large economic loss with an impact beyond the immediate influence on the directly affected agricultural producers. The outbreak emphasizes the need for collaboration between veterinary and health authorities, entomologists, environmental specialists, and biologists, as the best strategy towards the prevention and control of RVF.

Place, publisher, year, edition, pages
San Francisco, CA: Public Library of Science , 2011. Vol. 5, no 9, e1229
National Category
Clinical Medicine
Identifiers
URN: urn:nbn:se:umu:diva-48991DOI: 10.1371/journal.pntd.0001229ISI: 000296578900004PubMedID: 21980543OAI: oai:DiVA.org:umu-48991DiVA: diva2:452537
Available from: 2011-10-31 Created: 2011-10-31 Last updated: 2016-10-31Bibliographically approved
In thesis
1. Rift Valley fever: challenges and new insights for prevention and control using the “One Health” approach
Open this publication in new window or tab >>Rift Valley fever: challenges and new insights for prevention and control using the “One Health” approach
2016 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Rift Valley fever (RVF) is an emerging viral zoonosis that causes frequent outbreaks in east Africa and on the Arabian Peninsula. The likelihood of RVF global expansion due to climate change and human anthropogenic factors is an important issue. The causative agent, RVF virus, is an arbovirus that is transmitted by several mosquito species and is able to infect a wide range of livestock as well as people. The infection leads to mass abortions and death in livestock and a potentially deadly hemorrhagic fever in humans. RVF has severe socio-economic consequences such as animal trade bans between countries, disruption of food security, and economic disaster for farmers and pastoralists as well as for countries. Human behavior such as direct contact with infected animals or their fluids and exposure to mosquito bites increases the risk for contracting the disease.

To better understand the challenges associated with RVF outbreaks and to explore prevention and control strategies, we used the One Health approach. The local community had to be involved to understand the interaction between the environment, animals, and humans. We focused on Sudan, Saudi Arabia, and Kenya. First, we systematically reviewed the literature and then we performed cross sectional community-based studies using a special One Health questionnaire. Climatic and remote sensing data were used in combination with statistics to develop a sub-region predictive model for RVF.

For both Saudi Arabia and Sudan, the ecology and environment of the affected areas were similar. These areas included irrigation canals and excessive rains that provide an attractive habitat for mosquito vectors to multiply. The surveillance systems were unable to detect the virus in livestock before it spread to humans. Ideally, livestock should serve as sentinels to prevent loss of human lives, but the situation here was reversed. Differences between countries regarding further spread of RVF was mainly determined by better economic and infrastructure resources.

In Sudan, there was a lack of knowledge and appropriate practices at the studied community regarding RVF disease symptoms and risk factors for both animals and humans. The community was hesitant in notifying the authorities about RVF suspicion in livestock due to the lack of a compensation system. The perceived role of the community in controlling RVF was fragmented, increasing the probability of RVF transmission and disease.

In Kenya, our study found that better knowledge about RVF does not always translate to more appropriate practices that avoid exposure to the disease. However, the combination of good knowledge, attitudes, and practices may explain why certain communities were less affected. Strategies to combat RVF should consider socio-cultural and behavioral differences among communities. We also noticed that RVF outbreaks in Kenya occurred in regions with high livestock density exposed to heavy rains and wet soil fluxes, which could be measured by evapotranspiration and vegetation seasonality variables. We developed a RVF risk map on a sub-regional scale. Future outbreaks could be better managed if such relevant RVF variables are integrated into early warning systems.

To confront RVF outbreaks, a policy is needed that better incorporates ecological factors and human interactions with livestock and environment that help the RVF pathogen spread. Early detection and notification of RVF is essential because a delay will threaten the core of International Health Regulations (IHR), which emphasizes the share of information during a transboundary disease outbreak to avoid unnecessary geographical expansion.

Place, publisher, year, edition, pages
Umeå: Umeå University, 2016. 39 p.
Series
Umeå University medical dissertations, ISSN 0346-6612 ; 1858
Keyword
Rift Valley fever, Sociocultural practices, Community involvement, Ecological factors, Risk map, Early warning system, Surveillance system, International Health Regulations, and One Health approach.
National Category
Public Health, Global Health, Social Medicine and Epidemiology
Research subject
Epidemiology; Public health
Identifiers
urn:nbn:se:umu:diva-127095 (URN)978-91-7601-597-1 (ISBN)
Public defence
2016-11-22, Betula, NUS 6M - Laboratoriecentrum, Betula, Umeå, 09:00 (English)
Opponent
Supervisors
Available from: 2016-11-01 Created: 2016-10-28 Last updated: 2016-11-01Bibliographically approved

Open Access in DiVA

fulltext(359 kB)8 downloads
File information
File name FULLTEXT01.pdfFile size 359 kBChecksum SHA-512
5cf49c044b57dc4f89f217caebffd706f0134dfddc41c10b3fa962f7157fe78cf8afc7d621fc48ddbbd8b74d55336a12a89c8171dfeb071c8e54138034d8dd24
Type fulltextMimetype application/pdf

Other links

Publisher's full textPubMed

Search in DiVA

By author/editor
Hassan, Osama AhmedAhlm, ClasEvander, Magnus
By organisation
Infectious DiseasesVirology
In the same journal
PLoS Neglected Tropical Diseases
Clinical Medicine

Search outside of DiVA

GoogleGoogle Scholar
Total: 8 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 107 hits
ReferencesLink to record
Permanent link

Direct link