<< Back To HomeCSU 07/2010: THREE ON TRACHOMA CONTROL
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CSU 07/2010: THREE ON TRACHOMA CONTROL
1) MASS DISTRIBUTION OF ORAL AZITHROMYCIN AGAINST INFECTIOUS TRACHOMA
This often cited article from Ethiopia shows that mass administration of
azithromycin led to temporary declines in infectious trachoma in rural
Ethiopia. Evidence from Ethiopia and elsewhere suggests that repeated
administration of azithroymcin is necessary to achieve durable declines in
infectious trachoma.
Am I correct in believing that no country has thus far tried to integrate
azithromycin administration into Child Health Days? There are economies to
be realized if this vertical intervention is integrated into a multipurpose
delivery platform.
Full text, with graphics, is at
http://www.plosntds.org/article/info%3Adoi%2F10.1371%2Fjournal.pntd.0000376
PLoS Negl Trop Dis. 2009;3(2):e376. Epub 2009 Feb 3.
Reduction and return of infectious trachoma in severely affected
communities in Ethiopia.
Lakew T, House J, Hong KC, Yi E, Alemayehu W, Melese M, Zhou Z, Ray K, Chin
S, Romero E, Keenan J, Whitcher JP, Gaynor BD, Lietman TM.
Orbis International, Addis Ababa, Ethiopia.
BACKGROUND: Antibiotics are a major tool in the WHO's trachoma control
program. Even a single mass distribution reduces the prevalence of the
ocular chlamydia that causes trachoma. Unfortunately, infection returns
after a single treatment, at least in severely affected areas. Here, we
test whether additional scheduled treatments further reduce infection, and
whether infection returns after distributions are discontinued.
METHODS: Sixteen communities in Ethiopia were randomly selected. Ocular
chlamydial infection in 1- to 5-year-old children was monitored over four
biannual azithromycin distributions and for 24 months after the last
treatment.
FINDINGS: The average prevalence of infection in 1- to 5-year-old children
was reduced from 63.5% pre-treatment to 11.5% six months after the first
distribution (P<0.0001). It further decreased to 2.6% six months after the
fourth and final treatment (P = 0.0004). In the next 18 months, infection
returned to 25.2%, a significant increase from six months after the last
treatment (P = 0.008), but still far lower than baseline (P<0.0001).
Although the prevalence of infection in any particular village fluctuated,
the mean prevalence of the 16 villages steadily decreased with each
treatment and steadily returned after treatments were discontinued.
CONCLUSION: In some of the most severely affected communities ever studied,
we demonstrate that repeated mass oral azithromycin distributions
progressively reduce ocular chlamydial infection in a community, as long as
these distributions are given frequently enough and at a high enough
coverage. However, infection returns into the communities after the last
treatment. Sustainable changes or complete local elimination of infection
will be necessary.
2) Assessment of herd protection against trachoma due to repeated mass
antibiotic distributions: a cluster-randomised trial.
Lancet. 2009 Mar 28;373(9669):1111-8.
House JI, Ayele B, Porco TC, Zhou Z, Hong KC, Gebre T, Ray KJ, Keenan JD,
Stoller NE, Whitcher JP, Gaynor BD, Emerson PM, Lietman TM.
FI Proctor Foundation, University of California, San Francisco, USA.
Comment in:
Lancet. 2009 Aug 8;374(9688):449; author reply 449-50.
Lancet. 2009 Mar 28;373(9669):1061-3.
BACKGROUND: Trachoma-control programmes distribute oral azithromycin to
treat the ocular strains of chlamydia that cause the disease and to control
infection.
Theoretically, elimination of infection is feasible if untreated
individuals receive an indirect protective effect from living in repeatedly
treated
communities, which is similar to herd protection in vaccine programmes. We
assessed indirect protection against trachoma with mass azithromycin
distributions.
METHODS: In a cluster randomised trial, 24 subkebeles (government-defined
units) in Amhara, Ethiopia, were randomised, with use of a
simple random sample, to distribution four times per year of single-dose
oral azithromycin to children aged 1-10 years (12 subkebeles, 4764
children), or to delayed treatment until after the study (control; 12
subkebeles, 6014 children).
We compared the prevalence of ocular chlamydial infection in untreated
individuals 11 years and older between baseline and 12 months in the
treated subkebeles, and at 12 months between the treated and control
subkebeles.
Health-care and laboratory personnel were blinded to study group. Analysis
was intention to treat. The study is registered with clinicaltrials.gov,
number NCT00322972.
FINDINGS: At 12 months, 637 children aged 1-10 years and 561 adults and
children aged 11 years and older were analysed in the children-treated
group, and 618 and 550, respectively, in the control group. The mean
prevalence of infection in children decreased from 48.4% (95% CI 42.9-53.9)
to 3.6% (0.8-6.4) after four mass treatments. At 12 months, the mean
prevalence of infection in the untreated age group (/=11 years) was 47%
(95% CI 33-57) less than baseline (p=0.002), and 35% (95% CI 1-57) less
than that in untreated communities
(p=0.04).
INTERPRETATION: Frequent treatment of children, who are a core group for
transmission of trachoma, could eventually eliminate infection from the
entire community. Herd protection is offered by repeated mass antibiotic
treatments, providing a strategy for elimination of a bacterial disease
when an effective vaccine is unavailable.
FUNDING: National Institutes of Health.
3) Evaluation of three years of the SAFE Strategy for Trachoma Control in
Five Districts of Ethiopia
Trans R Soc Trop Med Hyg. 2009 Oct;103(10):1001-10. Epub 2009 Jan 28.
Evaluation of three years of the SAFE strategy (Surgery, Antibiotics,
Facial cleanliness and Environmental improvement) for trachoma control in
five districts of Ethiopia hyperendemic for trachoma.
Ngondi J, Gebre T, Shargie EB, Adamu L, Ejigsemahu Y, Teferi T, Zerihun M,
Ayele B, Cevallos V, King J, Emerson PM.
The Carter Center, 1 Copenhill Avenue, Atlanta, GA, USA. jn250@cam.ac.uk
Trachoma surveys were conducted at baseline in five districts of Amhara
National Regional State, Ethiopia (7478 participants in 1096 households)
and at 3-year evaluation (5762 participants in 1117 households).
Uptake of SAFE was assessed with programme monitoring data and interviews,
and children (1-6 years) were swabbed for detection of ocular Chlamydia. At
evaluation, 23,933 people had received trichiasis surgery; 93% of
participants reported taking azithromycin at least once; 67% of household
respondents (range 46-93) reported participation in trachoma health
education; and household latrine coverage increased from 2% to 34%.
In children aged 1-9 years percentage decline, by district, for outcomes
was: 32% (95% CI 19-48) to 88% (95% CI 83-91) for trachomatous
inflammation-follicular (TF); 87% (95% CI 83-91) to 99% (95% CI 97-100) for
trachomatous inflammation-intense (TI); and 31% increase (95% CI -42 to
-19) to 89% decrease (95% CI 85-93) for unclean face; and in adults
percentage decline in trichiasis was 45% (95% CI -13 to 78) to 92% (95% CI
78-96). Overall prevalence of swabs positive for ocular Chlamydia was 3.1%.
Although there were substantial reductions in outcomes in children and
adults, the presence of ocular Chlamydia and TF in children suggests
ongoing transmission. Continued implementation of SAFE is warranted.