Hepatitis A is a viral liver disease transmitted through ingestion of contaminated food, water, or direct contact. It affects over 1.4 million people globally each year. While symptoms can range from mild to severe, it is rarely fatal and does not typically cause chronic liver disease. Improved sanitation and vaccination are the most effective prevention methods. An analysis of South African surveillance data from January to March 2014 found the highest number of cases in KwaZulu-Natal and Western Cape provinces.
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Hepatitis A Cases in South Africa
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STATISTICAL NOTES NOVEMBER 2014
Welcome to this edition of Statistical Notes!
HEPATITIS A
1. Background
Hepatitis A is a viral liver disease that can cause mild to severe illness.
Globally, there are an estimated 1.4 million cases of hepatitis A every year.
The hepatitis A virus is transmitted through ingestion of contaminated food
and water or through direct contact with an infectious person1. Hepatitis A is
associated with a lack of safe water and poor sanitation. Epidemics can be
explosive and cause significant economic losses. Improved sanitation and the
hepatitis A vaccine are the most effective ways to combat the disease. Unlike
hepatitis B and C, hepatitis A infection does not cause chronic liver disease
and is rarely fatal, but it can cause debilitating symptoms and fulminant
hepatitis (acute liver failure), which is associated with high mortality.
Hepatitis A occurs sporadically and in epidemics worldwide, with a tendency
for cyclic recurrences. Every year there is an estimated 1.4 million cases of
hepatitis A worldwide. The hepatitis A virus is one of the most frequent causes
of food-borne infections2. Epidemics related to contaminated food or water
can erupt explosively, such as the epidemic in Shanghai in 1988 that affected
about 300 000 people. Hepatitis A viruses persist in the environment and can
resist food-production processes routinely used to inactivate and/or control
bacterial pathogens.
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The disease can lead to significant economic and social consequences in
communities. It can take weeks or months for people recovering from the
illness to return to work, school or daily life. The impact on food
establishments identified with the virus, and local productivity in general, can
be substantial.
2. Transmission
Hepatitis A is a liver disease caused by the hepatitis A virus. The virus is
primarily spread when an uninfected (and unvaccinated) person ingests food
or water that is contaminated with the faeces of an infected person. The
disease is closely associated with unsafe water, inadequate sanitation and
poor personal hygiene3. The hepatitis A virus is transmitted primarily by the
faecal-oral route; that is when an uninfected person ingests food or water that
has been contaminated with the faeces of an infected person. Waterborne
outbreaks, though infrequent, are usually associated with sewage-
contaminated or inadequately treated water. The virus can also be transmitted
through close physical contact with an infectious person, although casual
contact among people does not spread the virus.
Figure 1: Estimated Hepatitis A virus Prevalence
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3. Signs and symptoms
The incubation period of hepatitis A is usually 14–28 days. Symptoms of
hepatitis A range from mild to severe, and can include fever, malaise, loss of
appetite, diarrhea, nausea, abdominal discomfort, dark-coloured urine and
jaundice (a yellowing of the skin and whites of the eyes)4. Not everyone who
is infected will have all of the symptoms. Adults have signs and symptoms of
illness more often than children and the severity of disease and mortality
increases in older age groups. Infected children under six years of age do not
usually experience noticeable symptoms, and only 10% develop jaundice.
Among older children and adults, infection usually causes more severe
symptoms, with jaundice occurring in more than 70% of cases.
Table 1: Hepatitis A IgM positive cases by province, South Africa, 01
January to 31 March 2014
An overall of 896 Hepatitis A cases was recorded in South Africa for the
period Janaury to March 2014.
Table 1: Hepatitis A cases recorded in South Africa for the period
January to March 2014
Province Frequency %
Eastern Cape 108 12.1
Free State 31 3.5
Gauteng 180 20.1
KwaZulu-Natal 222 24.8
Limpopo 50 5.6
Mpumalanga 46 5.1
North West 43 4.8
Northern Cape 16 1.8
WesternCape 200 22.3
Total 896 100
Of these cases, highest proportions of 222 cases accounting for 25% was
recorded in KwaZulu Natal province then followed by Western Cape Province
with 22.3%.
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Figure 1: Table 1: Hepatitis A IgM positive cases by province, South
Africa, 01 January to 31 March 2014
Source: National laboratory Surveillance
North West Province and Northern Cape Province recorded the Hepatitis
A cases of less than 5%.
Figure 2: Hepatitis A IgM positive cases by province, South Africa, 01
January to 31 March 2014
Source: National laboratory Surveillance
4. Prevention
Improved sanitation, food safety and immunization are the most effective
ways to combat hepatitis A. The spread of hepatitis A can be reduced by
108
31
180
222
50 46 43
16
200
12.1 3.5
20.1 24.8
5.6 5.1 4.8 1.8
22.3
0
50
100
150
200
250
Province
%
EC, 12.1
GP, 20.1
KZN, 24.8LP, 5.6
MP, 5.1
NW, 4.8
NC, 1.8
WC, 22.3
EC
FS
GP
KZN
LP
MP
NW
NC
WC
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adequate supplies of safe drinking water, proper disposal of sewage within
communities and personal hygiene practices such as regular hand-washing
with safe water. Several hepatitis A vaccines are available internationally. All
are similar in terms of how well they protect people from the virus and their
side-effects. No vaccine is licensed for children younger than one year of age.
Nearly 100% of people develop protective levels of antibodies to the virus
within one month after a single dose of the vaccine. Even after exposure to
the virus, a single dose of the vaccine within two weeks of contact with the
virus has protective effects. Still, manufacturers recommend two vaccine
doses to ensure a longer-term protection of about five to eight years after
vaccination. Millions of people have been immunized worldwide with no
serious adverse events. The vaccine can be given as part of regular childhood
immunizations program and also with other vaccines for travelers.
5. Conclusion
Geographical distribution areas can be characterized as having high,
intermediate or low levels of hepatitis A infection. In developing countries with
very poor sanitary conditions and hygienic practices, most children (90%)
have been infected with the hepatitis A virus before the age of 10. Those
infected in childhood do not experience any noticeable symptoms5. Epidemics
are uncommon because older children and adults are generally immune.
Symptomatic disease rates in these areas are low and outbreaks are rare. In
developing countries, countries with transitional economies and regions where
sanitary conditions are variable, children often escape infection in early
childhood. Ironically, these improved economic and sanitary conditions may
lead to a higher susceptibility in older age groups and higher disease rates, as
infections occur in adolescents and adults, and large outbreaks can occur. In
developed countries with good sanitary and hygienic conditions, infection
rates are low. Disease may occur among adolescents and adults in high-risk
groups, such as injecting-drug users, men who have sex with men, people
travelling to areas of high endemicity, and in isolated populations such as
closed religious communities6.
Hepatitis A and B video
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Hepatitis A and B.mp4
6. BIBLIOGRAPHY
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and in international travelers. Updated recommendations of the Advisory
Committee on Immunization Practices (ACIP). MMWR Morb Mortal Wkly
Rep. 2007 Oct 19;56(41):1080–4.
3. CDC. Updated recommendations from the Advisory Committee on
Immunization Practices (ACIP) for use of hepatitis A vaccine in close
contacts of newly arriving international adoptees. MMWR Morb Mortal Wkly
Rep. 2009 Sep 18;58(36):1006–7.
4. CDC, Division of Viral Hepatitis. Viral hepatitis surveillance: United States,
2009. Atlanta: CDC; 2009 [cited 2012 Sep 20]. Available from:
http://www.cdc.gov/hepatitis/Statistics/2009Surveillance/PDFs/2009HepSur
veillanceRpt.pdf.
5. Fiore AE. Hepatitis A transmitted by food. Clin Infect Dis. 2004 Mar
1;38(5):705–15.
6. Fiore AE, Wasley A, Bell BP. Prevention of hepatitis A through active or
passive immunization: recommendations of the Advisory Committee on
Immunization Practices (ACIP). MMWR Recomm Rep. 2006 May 19;55(RR-
7):1–23.
7. Klevens RM, Miller JT, Iqbal K, Thomas A, Rizzo EM, Hanson H, et al. The
evolving epidemiology of hepatitis A in the United States: incidence and
molecular epidemiology from population-based surveillance, 2005–2007.
Arch Intern Med. 2010 Nov 8;170(20):1811–8.