A systematic review of Rift Valley Fever epidemiology 1931–2014

Figures & data

Fig. 1.  PRISMA flow chart diagram describing the studies selection process for inclusion in this review [adapted and modified from (19)].

Fig. 2.  Map of Africa and Arabian Peninsula illustrating the spatial and temporal distribution of Rift Valley status from the first suspected case in 1912. Total number of human deaths (HD) is indicated for selected countries for all outbreak periods. Based on (2, 5–7, 10–12, 14) (16, 22) (23, 25) (40, 46) (54, 75) (80).

Fig. 3.  Map of Africa and the Arabian Peninsula illustrating the spatial and temporal distribution of Rift Valley cumulative outbreaks in days from 1977 to 2012 (2, 5–7, 10–12, 22) (23, 25) (40, 46) (80).

Table 1 Characteristics of the eligible studies investigating RVF epidemiology, ecology, risk factors, and spatial modeling 1931–2012

				Morbidity and mortality estimates
				Animals		Humans
Year(s)	Geographic distribution	Study design	Research questions/objectives	Reported cases	Deaths	Reported cases	Deaths	Estimated impact in US$ (×10^6)	References
1931	Kenya	Cross-sectional	Risk factors and ecology	nd	4,700	nd	nd	nd	(25)
1950–1951	South Africa	Cross-sectional	Epidemiology and spatial modeling	600,000	100,000	nd	nd	nd	(22, 26) (31)
1977–1978	Egypt	Cross-sectional	Epidemiology and socioeconomics	nd	nd	200,000	598	115	(1, 32) (81)
1978	Zimbabwe	Cross-sectional	Risk factors	70,000	10,000	nd	nd	nd	(27, 31)
1988	Mauritania	Case–control	Risk factors	nd	nd	nd	224	nd	(9)
1987–1989	Senegal	Cohort	Molecular epidemiology	1,715	nd	273	16	nd	(28, 34)
1997–1998	Kenya Somalia Tanzania	Cross-sectional	Ecology, risk factors and socioeconomics	89,000 nd nd	478 nd nd	160,000 28,000 89,000	450 170 478	250^c 378^c nd	(2, 35) (82)
1998	Mauritania	Cross-sectional	Sero-epidemiology, entomology and virology	343	nd	90	1		(30)
2000	Saudi Arabia	Cross-sectional	Risk factors and ecology	>10,000	1,000	883	245	10	(36, 37)
2000–2001	Yemeni	Cross-sectional	Risk factors and socioeconomics	22,000	6,000	1,328	166	107	(5, 42) (81)
2003	Egypt	Cross-sectional	Risk factors and virology	nd	nd	45	17	nd	(33)
2007–2008	Sudan	Cross-sectional	Risk factors and ecology	nd	nd	75,000* (698)	222	nd	(6, 79) (80)
2008–2009	Madagascar	Cross-sectional	Epidemiology and socioeconomics	nd	nd	10,000 (712)	26	nd	(84)
2006–2007	Somalia Tanzania Kenya	Cross-sectional	Risk factors, predictive modeling and ecology	nd 32,000 nd	nd 4,200 nd	35,000* (114) 40,000* (264) 75,000* (684)	51 109 158	541^c	(21, 29) (39, 40) (48, 49) (52)
2010–2011	South Africa	Cross-sectional	Spatial and predictive modeling	14,342	8,877	242	26	nd	(22, 75) (84)
2012	Mauritania	Cross-sectional	Risk factors, molecular diversity	nd	343	41	17	nd	(8, 10) (11)

nd=no documented estimates; c=combined estimates.

*Estimated cases in brackets are the reported.

Moher D, Liberati A, Tetzlaff J, Altman DG, PRISMA Group . Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med. 2009; 151: 264–9.

 Google Scholar

Woods CW, Karpati AM, Grein T, McCarthy N, Gaturuku P, Muchiri E, etal. An outbreak of Rift Valley fever in Northeastern Kenya, 1997–98. Emerg Infect Dis. 2002; 8: 138–44.

 PubMed Web of Science ®Google Scholar

Abdo-Salem S, Gerbier G, Bonnet P, Al-Qadasi M, Tran A, Thiry E, etal. Descriptive and spatial epidemiology of Rift Valley fever outbreak in Yemen 2000–2001. Ann N Y Acad Sci. 2006; 1081: 240–2.

 Web of Science ®Google Scholar

Sissoko D, Giry C, Gabrie P, Tarantola A, Pettinelli F, Collet L, etal. Rift Valley fever, Mayotte, 2007–2008. Emerg Infect Dis. 2009; 15: 568–70.

 Web of Science ®Google Scholar

Sow A, Faye O, Ba Y, Ba H, Diallo D, Faye O, etal. Rift Valley fever outbreak, Southern Mauritania, 2012. Emerg Infect Dis. 2014; 20: 2012–15.

 Web of Science ®Google Scholar

Ikegami T. Molecular biology and genetic diversity of Rift Valley fever virus. Antiviral Res. 2012; 95: 293–310.

 PubMed Web of Science ®Google Scholar

Anyamba A, Linthicum KJ, Small J, Britch SC, Pak E, de La Rocque S, etal. Prediction, assessment of the Rift Valley fever activity in East and Southern Africa 2006–2008 and possible vector control strategies. Am J Trop Med Hyg. 2010; 83(2 Suppl): 43–51.

 Web of Science ®Google Scholar

Indeje M, Ward MN, Ogallo LJ, Davies G, Dilley M, Anyamba A. Predictability of the normalized difference vegetation index in Kenya and potential applications as an indicator of Rift Valley fever outbreaks in the greater horn of Africa. J Clim. 2006; 19: 1673–87.

 Web of Science ®Google Scholar

Pienaar NJ, Thompson PN. Temporal and spatial history of Rift Valley fever in South Africa: 1950 to 2011. Onderstepoort J Vet Res. 2013; 80: 384.

 Web of Science ®Google Scholar

Bird BH, Ksiazek TG. Rift Valley fever virus. J Am Vet Med Assoc. 2009; 234: 883–93.

 PubMed Web of Science ®Google Scholar

Daubney R, Hudson JR, Garnham PC. Enzootic hepatitis or Rift Valley fever. An undescribed virus disease of sheep cattle and man from east Africa. J Pathol Bacteriol. 1931; 34: 545–79.

 Google Scholar

Munyua P, Murithi RM, Wainwright S, Githinji J, Hightower A, Mutonga D, etal. Rift Valley fever outbreak in livestock in Kenya, 2006–2007. Am J Trop Med Hyg. 2010; 83(2 Suppl): 58–64.

 PubMed Web of Science ®Google Scholar

Sindato C, Karimuribo ED, Pfeiffer DU, Mboera LEG, Kivaria F, Dautu G, etal. Spatial and temporal pattern of Rift Valley fever outbreaks in Tanzania; 1930 to 2007. PLoS One. 2014; 9: e88897.

 PubMed Web of Science ®Google Scholar

Magona JW, Galiwango T, Walubengo J, Mukiibi G. Rift Valley fever in Uganda: seroprevalence and risk factor surveillance vis-à-vis mosquito vectors, anti-RVF virus IgG and RVF virus neutralizing antibodies in goats. Small Rumin Res. 2013; 114: 176–81.

 Web of Science ®Google Scholar

Métras R, Porphyre T, Pfeiffer DU, Kemp A, Thompson PN, Collins LM, etal. Exploratory space-time analyses of Rift Valley fever in South Africa in 2008–2011. PLoS Negl Trop Dis. 2012; 6: e1808.

 Web of Science ®Google Scholar

Watts D, El-Tigani A, Botros B, Salib A, Olson J, McCarthy M, etal. Arthropod-borne viral infections associated with a fever outbreak in the northern province of Sudan. J Trop Med Hyg. 1994; 97: 228–30. [PubMed Abstract].

 Google Scholar

Coetzer JW. The pathology of Rift Valley fever. Lesions occurring in field cases in adult cattle, calves and aborted fetuses. Onderstepoort J Vet Res. 1981; 49: 11–17.

 Web of Science ®Google Scholar

Swanepoel RCJ, Coetzer JAW, Thompson GR, Tustin RD. Rift Valley fever. Infectious diseases of livestock with special reference to southern Africa. 1994; Cape Town, South Africa: Oxford University Press. 1037–70. 2nd ed.

 Google Scholar

Imam IZE, Darwish MA, El-Karamany R. An epidemic of Rift Valley fever in Egypt. 1. Diagnosis of Rift Valley fever in man. Bull World Health Organ. 1979; 57: 437–9. [PubMed Abstract] [PubMed CentralFull Text].

 Google Scholar

Meegan JM. The Rift Valley fever epizootic in Egypt 1977–78. Description of the epizootic and virological studies. Trans R Soc Trop Med Hyg. 1979; 73: 618–23.

 PubMed Web of Science ®Google Scholar

Peyre M, Chevalier V, Abdo-Salem S, Velthuis A, Antoine-Moussiaux N, Thiry E, etal. A systematic scoping study of the socio-economic impact of Rift Valley fever: research gaps and needs. Zoonoses Public Health. 2015; 62: 309–25.

 PubMed Web of Science ®Google Scholar

Swanepoel R. Observations on Rift Valley fever in Zimbabwe. Contrib to Epidemiol Biostat. 1981; 3: 83–91.

 Google Scholar

Jouan A, Le Guenno B, Digoutte J, Philippe B, Riou O, Adam F. An RVF epidemic in southern Mauritania. Ann Inst Pasteur Virol. 1988; 139: 307–8.

 PubMedGoogle Scholar

Guillaud M, Le Guenno B, Wilson ML, Desoutter D, Gonzalez JP, Digoutte JP. Prevalence of antibodies against Rift Valley fever virus in sheep and goats in Senegal. Ann Inst Pasteur Virol. 1988; 139: 455–9.

 Google Scholar

Wilson ML, Chapman LE, Hall DB, Dykstra EA, Ba K, Zeller HG, etal. Rift Valley fever in rural northern Senegal: human risk factors and potential vectors. Am J Trop Med Hyg. 1994; 50: 663–75. [PubMed Abstract].

 Google Scholar

CDC. Rift Valley fever – East Africa, 1997–1998. Morb Mortal Wkly Rep. 1998; 43: 261–4.

 Google Scholar

Soumaré B, Thys E, Berkvens D, Hashi A, Van Huylenbroeck G. Effects of livestock import bans imposed by Saudi Arabia on Somaliland for sanitary reasons related to Rift Valley fever. Outlook Agric. 2006; 35: 19–24.

 Web of Science ®Google Scholar

Nabeth P, Kane Y, Abdalahi MO, Diallo M, Ndiaye K, Ba K, etal. Rift Valley fever outbreak, Mauritania, 1998: seroepidemiologic, virologic, entomologic, and zoologic investigations. Emerg Infect Dis. 2001; 7: 1052–4.

 PubMed Web of Science ®Google Scholar

Madani TA, Al-Mazrou YY, Al-Jeffri MH, Mishkhas AA, Al-Rabeah AM, Turkistani AM, etal. Rift Valley fever epidemic in Saudi Arabia: epidemiological, clinical, and laboratory characteristics. Clin Infect Dis. 2003; 37: 1084–92.

 PubMed Web of Science ®Google Scholar

Al-Hazmi M, Ayoola EA, Abdurahman M, Banzal S, Ashraf J, El-Bushra A, etal. Epidemic Rift Valley fever in Saudi Arabia: a clinical study of severe illness in humans. Clin Infect Dis. 2003; 36: 245–52.

 PubMed Web of Science ®Google Scholar

Ahmad K. More deaths from Rift Valley fever in Saudi Arabia and Yemen. Lancet. 2000; 356: 1422.

 PubMed Web of Science ®Google Scholar

CDC. Rift Valley fever, Egypt. Wkly Epidemiol Rec. 2003; 78: 313–20.

 Google Scholar

Hassan O, Ahlm C, Sang R, Evander M. The 2007 Rift Valley fever outbreak in Sudan. PLoS Negl Trop Dis. 2011; 5: e1229.

 PubMed Web of Science ®Google Scholar

Hassan O, Ahlm C, Evander M. A need for one health approach – lessons learned from outbreaks of Rift Valley fever in Saudi Arabia and Sudan. Infect Ecol Epidemiol. 2014; 4: 1–8.

 Google Scholar

Dar O, McIntyre S, Hogarth S, Heymann D. Rift Valley fever and a new paradigm of research and development for zoonotic disease control. Emerg Infect Dis. 2013; 19: 189–93.

 PubMed Web of Science ®Google Scholar

Sindato C, Swai E, Karimuribo E, Dautu G, Pfeiffer D, Mboera L. Spatial distribution of non-clinical Rift Valley fever viral activity in domestic and wild ruminants in northern Tanzania. Tanzania Vet J. 2013; 28: 21–38.

 Google Scholar

WHO. Outbreaks of Rift Valley fever in Kenya, Somalia and United Republic of Tanzania, December 2006–April 2007. Wkly Epidemiol Rec. 2007; 82: 169–78.

 Google Scholar

Anyangu AS, Gould LH, Sharif SK, Nguku PM, Omolo JO, Mutonga D, etal. Risk factors for severe Rift Valley fever infection in Kenya, 2007. Am J Trop Med Hyg. 2010; 83(2 Suppl): 14–21.

 PubMed Web of Science ®Google Scholar

LaBeaud AD, Muchiri EM, Ndzovu M, Mwanje MT, Muiruri S, Peters CJ, etal. Interepidemic Rift Valley fever virus seropositivity, northeastern Kenya. Emerg Infect Dis. 2008; 14: 1240–6.

 PubMed Web of Science ®Google Scholar

Nguku PM, Sharif SK, Mutonga D, Amwayi S, Omolo J, Mohammed O, etal. An investigation of a major outbreak of Rift Valley fever in Kenya: 2006–2007. Am J Trop Med Hyg. 2010; 83(2 Suppl): 5–13.

 PubMed Web of Science ®Google Scholar

Mohamed M, Mosha F, Mghamba J, Zaki SR, Shieh W-J, Paweska J, etal. Epidemiologic and clinical aspects of a Rift Valley fever outbreak in humans in Tanzania, 2007. Am J Trop Med Hyg. 2010; 83(2 Suppl): 22–7.

 Web of Science ®Google Scholar

Jäckel S, Eiden M, El Mamy BO, Isselmou K, Vina-Rodriguez A, Doumbia B, etal. Molecular and serological studies on the Rift Valley fever outbreak in Mauritania in 2010. Transbound Emerg Dis. 2013; 60(Suppl 2): 31–9.

 Web of Science ®Google Scholar

WHO . Rift Valley Fever in Mauritania. 2012; Geneva, Switzerland: World Health Organization.

 Google Scholar