NON EBOLA OUTBREAKS
VIRAL HEMORRHAGIC FEVER OUTBREAKS
Ebola is one of the many fatal viral hemorrhagic fevers. VHF is a multi system syndrome caused by several distinct family of viruses usually resulting in vascular system damage and hemorrhage. It is caused by four distinct family of RNA viruses. These viruses are usually geographically restricted. Outbreaks caused by these viruses occur irregularly and cannot be predicted easily.
Figure 1 shows the table about the family of Hemorrhagic fever viruses
FAMILY OF VIRUSES
These diseases are usually endemic and are spread to other regions only when the host is exported. Some of these like Marburg, Crimean – Congo are as severe as Ebola , whereas some of them are not fatal.
Among the several VHF, four notable VHF can be imported to Australia (Department of Health & Human Services, 2015) they are :
Lassa fever
Crimean-congo
Marburg
Ebola
HISTORY AND PAST OUTBREAKS
MARBURG VIRUS
First identified in the year 1967 when the German Institute of Marburg was doing polio research using a monkey from Uganda which resulted in the death of 7 people.Since then 12 outbreaks were observed across the sub Saharan Africa resulting in almost 400 deaths.
FIGURE 2. THE GEOGRAPHICAL DISTRIBUTION OF MARBURG VIRUS (World Health Organization, 2018)
After the 1998 outbreak in the Democratic Republic of Congo (mortality 83%) Marburg outbreak in Angola was declared as the worst outbreak killing almost 227 people ( 90% mortality).
YELLOW FEVER
First yellow fever outbreak occurred in late 1690’s although researcher’s says it has been evolved 3000 years ago in Africa. Largest epidemic outbreak occurred in 1793 when Caribbean refuges moved to Philadelphia. It resulted in the death of 5000 people with around 100 people dying each day.
Although vaccines are available these days , around 20,000 people per year are affected by this. Approximately 30 outbreaks are recorded up to date.
RIFT VALLEY FEVER
It was first identified in the year 1931 during an epidemic investigation among sheep in the Rift Valley of Kenya.
Major outbreaks
In 1977, 20,000-40,000 illness with 600 deaths was observed in Egypt due to trade of infected livestock via Nile irrigation system.
Largest documented outbreak was observed in the year 1997-1998 involving 5 countries resulting in approximately 90,000 cases following the El Nino event.
First outside Africa outbreak occurred in Saudi in the year 2000.
DENGUE
It was first recognized in the year 1950’s in Philippines and Thailand.During the years1967,1970,1982,1988 outbreaks due to four different strains of the dengue virus took place.
In 2015 Delhi, India faced the worst outbreak with 15,000 hospitalized cases.In 2017 Srilanka faced a similar situation killing 300 people(Jazeera, A., 2017)
The year 2016 was marked with large dengue outbreaks worldwide.
Table 1 shows the dengue outbreaks in the year 2016 (WHO, n.d)
LASSA FEVER
It was first identified in the year 1969 in Lassa , Nigeria . The index case was an American missionary nurse and 2 secondary cases where also identified.
Since 2000 there have been 25 outbreaks of this disease with the recent outbreak listed as the worst outbreak. This unprecedented outbreak has sickened 365 people and killed 81 since 1st of January 2018 (Maxmen, A., 2018)
CRIMEAN -CONGO FEVER
This arboviral disease was first identified in 1944 and the first human infection was reported in the year 1976.
Many outbreaks have been reported involving human infections in many countries including Albania (2001), Turkey (2002) ,Georgia (2009).An outbreak of both CCF and dengue was reported in the year 2010 in Pakistan , around 1500 cases was recorded (Zeller et al. 2007)
CONCLUSION
Thus it is clear that some non-ebola outbreaks are also as severe as Ebola . These outbreaks are reported to be epidemic and seasonal ( mostly during winter).With proper community engagement these outbreaks can be controlled.
REFERENCES
Department of Health & Human Services, 2015, Viral haemorrhagic fevers, State Government of Victoria, viewed 15 March 2018,
< https://www2.health.vic.gov.au/public-health/infectious-diseases/disease-information-advice/viral-haemorrhagic-fever>
Jazeera, A., 2017.,Worst-ever dengue outbreak kills up to 300 in Sri Lanka. Sri Lanka News | Al Jazeera, viewed 17 March 2018,
< https://www.aljazeera.com/news/2017/07/worst-dengue-outbreak-kills-300-sri-lanka-170724211025407.html>
Anon, Dengue and severe dengue. World Health Organization, viewed 17 March 2018,
<http://www.who.int/mediacentre/factsheets/fs117/en/>
Maxmen, A., 2018, Deadly Lassa-fever outbreak tests Nigeria's revamped health agency,Nature News, viewed 16 March 2018,
< https://www.nature.com/articles/d41586-018-03171-y>
Aradaib, I., Erickson, B., Mustafa, M., Khristova, M., Saeed, N., Elageb, R. and Nichol, S 2018, ‘ Nosocomial Outbreak of Crimean-Congo Hemorrhagic Fever, Sudan’.
Anyamba, A., Chretien, J., Small, J., Tucker, C., Formenty, P., Richardson, J., Britch, S., Schnabel, D., Erickson, R. and Linthicum, K. 2018, ‘Prediction of a Rift Valley fever outbreak’.