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According to local media reports the total number of
diagnosed cholera cases in Mozambique has risen to 524
with 14 deaths confirmed by the Ministry of Health. The
number of diagnosed cholera cases continues to rise in
Maputo. On 14 January 104 new cases entered the cholera
treatment ward in the city’s Mavalane General Hospital
bringing the number of people receiving treatment there
to 215, up from 173 the previous day. Meanwhile, there
were 25 new cases in Mozambique’s second largest city of
Beira making a total of 208 in Sofala province; most of
them in Beira. One more case has been diagnosed in
Massingir district bringing the total in the southern
province of Gaza to 101.
Cholera is mainly contracted through consumption of food
or water contaminated with the Vibrio cholerae
bacterium. Epidemics are linked to poor hygiene,
overcrowding, inadequate sanitation and unsafe water.
While current campaigns, which focus on providing care
to the sick and providing safe water, can prevent many
deaths, the lack of strong preventive measures means the
disease is still a major public health problem in some
50 resource-poor countries, according to the World
Health Organisation (WHO). Currently there are two types
of safe and effective oral cholera vaccines (OCVs). The
first consists of killed whole-cell V.cholerae 01 with
purified cholera toxin. After two doses in consecutive
weeks patients have high protection lasting for at least
one year. The second vaccine consists of a single dose
of attenuated live genetically modified V.cholerae 01
strain.
A mass vaccination project is being conducted in Beira,
which has particularly high levels of cholera. In 1999
the country reported 45 000 cholera cases, and Beira
alone has had between 3 880 and 4 880 cases per year
over the last three years. The vaccination campaign will
finish at the end of January 2004, with about 50 000
people vaccinated. The first results of this mass
vaccination campaign will be obtained within a year. The
Swedish Biological Laboratory (SBL) has donated the
vaccine for the trial and the International Federation
of Football Associations (FIFA) has supported the cost
of the trial.
The mass cholera vaccination ended with 81.7% of those
who took the first dose of the oral vaccine in December
2003 returning for the second dose. According to Deputy
National Health Director this can be
regarded as a success because in general, when vaccines
involve two doses, only 70-72% of those who took the
first dose return for the second. In absolute figures,
53 980 people took the first dose and
44 111 came back
for the second.
The vaccine was administered in the Beira neighbourhood
of Esturro, and the director hoped that it would protect
at least 60% of people in the neighbourhood against
cholera for the next two or three years. "If the vaccine
proves effective, the possibility will be open for
expanding its use to other areas at risk of cholera
outbreaks", he noted, pointing out that vaccination is
much cheaper than treatment. This programme will gauge
the efficacy of mass oral vaccination over an 11-month
period to determine whether this could be an effective
preventive measure.
The vaccination project is being conducted by the WHO in
collaboration with the Ministry of Health, Médecins sans
Frontières (MSF), Epicentre and the International
Vaccine Institute, with donor support from SBL and FIFA.
According to a WHO statement the cholera vaccine "has
been available for 10 years, but this is the first time
it has been used so broadly to minimise the devastation
of a cholera outbreak. It is also the first time that
WHO has considered the use of the oral cholera vaccine
as part of an overall strategy to control the disease".
In recent years, the number of reported cholera cases
worldwide has varied between 110 000 and 200 000 cases
per year. While official figures put deaths from cholera
at 5 000 a year, the WHO estimates that the true number
is probably significantly higher due to under-reporting
of cases and gaps in surveillance.
Keeping cholera victims alive in special cholera wards
costs 30 to 35 US $ per patient per day excluding staff
costs. The oral vaccine has given good results on a
limited scale in India and Afghanistan, but the Beira
experiment was the first time that it had been
administered to an entire population. The results will
be important, not only for Mozambique, but for many
other developing countries where cholera is a serious
threat. The challenge facing the health authorities now,
the deputy director said, is to follow up those who took
the vaccine and check that they really are immune to
cholera.
The basic precaution against cholera – ensuring that
drinking water is clean – seem quite easy and can be
achieved by boiling water, which kills the micro-
organisms that cause cholera. But this is far from
simple in poor urban neighbourhoods. Some cholera
victims interviewed by AIM in the Mavalane treatment
centre admitted that they did not boil their water
because of the cost of firewood or charcoal. Though it
is unlikely that combining traditional prevention
strategies with OCVs will eliminate cholera, there is
now greater potential to significantly decrease the
disease's incidence in high-risk populations. The public
health system may soon have another tool at its disposal
to fight cholera, one that will certainly save many
lives. |
