•
Are
diseases which are being identified among human beings for the first time or,
having been progressively getting better controlled, have started to show
rising incidences or to appear in places where they did not exist before.
•
Include:
AIDS (1981); SARS (March 2003); Lassa (1950s, 1969); Marbug (1967); Ebola
(1976); Legionellosis (Penn., 1976); Lyme (Conn., 1977); Rift Valley; West
Nile; Venezuelan equine encephalitis; etc.
•
Then,
Tuberculosis; Dengue; (Buruli & Yaws); Malaria, Yellow fever, Drug
resistant STIs; E coli; Salmonella; Influenza.
HIV/AIDS
•
Origin,
virus types, modes of transmission, window period, incubation/latency period,
curability; “a development crisis in Africa”.
•
Problems
with prevention: venereal shame, double-dealing, “stigma”; poverty; cost of
care, etc.
•
Control:
behavioural change, mass education, family and community support, international
support, etc; the condoms pros and cons.
SERIOUS
ACUTE RESPIRATORY SYNDROME
•
First
cases in March 2003 in China.
•
Present
with fever, cough, chest pain, dyspnoea, lobar consolidation, etc. Study show
it to be due to corona virus.
•
Control
so far by isolation, surveillance and symptomatic treatment.
•
Safety
assurance for laboratory procedures involving the specimens.
LASSA FEVER
•
Outbreaks
started to occur in the 1950s but it was not till the attack on American
missionaries and the isolation of the virus in 1969 that the name was given;
endemic disease of West Africa.
•
Reservoir
in rat (Mystomys natalensis).
•
Transmission
by contamination with rat excreta or direct blood or secretion of sufferer.
•
Control
by isolation, contact surveillance & post-exposure prophylaxis with
ribavirin; barrier nursing; rat control.
MARBUG
VIRAL DISEASE
•
First
cases in 1967 in Marbug, West Germany by contamination with blood, organs and
cell cultures of African Green monkeys.
•
Several
cases have been seen from East and Central Africa.
•
Reservoir-host-vector
chain yet undetermined.
•
Incubation
of 3 – 9 days
•
Control
essentially as for Lassa fever.
EBOLA
HAEMORRHAGIC FEVER.
•
A
haemorrhagic fever of East and Central African countries (Congo, etc) that
started in 1976.
•
Viral
cause of the same family as Marbug.
•
Transmission
by contact with blood or secretions of infected person; but
reservoir-vector-host factors not yet fully determined.
•
Control
as for Lassa except for unknown reservoir and vectors; and not sensitive to
ribavirin.
TUBERCULOSIS
•
Re-emerging
as a result of real time deterioration of health and human conditions,
rich-poor gap, urban migration and growth in urban slums, multi-drug resistance
phenomenon.
•
Epidemiology
otherwise as before.
•
Association
with silicosis and HIV/AIDS.
•
Control
programme by the DOTS; social rehabilitation also.
DENGUE
FEVER
•
Disease
of South-East Asia and the Western Pacific which got to pandemics involving the
Caribbean in 1977. Got to Nigeria with the trade in used tyres from the far
East 70s and 80s.
•
Normal
epidemiology in the endemic countries; and yet unclear in the others.
•
Control
essentially in vector (Aedes egypti) control; no vaccine as yet.
OTHER
RE-EMERGING DISEASES
•
Buruli
ulcer by Mycobacterium ulcerans, not a major emerging disease and
epidemiological basis most likely related to other mycobacteria. Control by
ulcer excision, early dressing, hygiene
•
Leprosy
by Mycobacterium leprae with epid. Virtually as for TB with more social stigma.
Control by single dose rifampicin, ofloxacin
and minocycline for paucibacillary infection; daily dapsone + monthly
rifampicine for 6 months; and daily dapsone + clofazimine and supervised
rifampicin + clofazimine monthly for 12 months. BCG, contact tracing + Rx;
social rehabilitation
•
TB
control by directly observed multidrug treatment strategy;
INH+rifampicin+pyrazinimide+ethambutol daily for 2months + isoniazid+rifampicin
3ice wkly for another 4 months
HEALTH
SERVICES AND CONTROL OF EMERGING AND RE-EMERGING DX
•
Essential
community health services for effective disease control, including the emerging
diseases.
•
Slide
2 and look at the other diseases there.
ARTICLE SOURCE
Prof. MC Asuzu,
Dept. of Community Medicine,
UCH, Ibadan.