Epidemiology of giardiasis and assemblages A and B and effects on diarrhea and growth trajectories during the first 8 years of life: Analysis of a birth cohort in a rural district in tropical Ecuador

BACKGROUND

There are limited longitudinal data on the acquisition of Giardia lamblia infections in childhood using molecular assays to detect and type assemblages, and measure effects of infections on diarrhea risk and childhood growth.

METHODS

We analysed stool samples from a surveillance sample within a birth cohort in a rural district in tropical Ecuador. The cohort was followed to 8 years of age for the presence of G. lamblia in stools by quantitative PCR and A and B assemblages by Taqman assay or Sanger sequencing. We explored risk factors associated with infection using generalized estimating equations applied to longitudinal binary outcomes, and longitudinal panel data analysis to estimate effects of infection on diarrhea and growth trajectories.

RESULTS

2,812 stool samples collected between 1 month and 8 years of age from 498 children were analyzed and showed high rates of infection: 79.7% were infected at least once with peak prevalence (53.9%) at 5 years. Assemblage B was accounted for 56.8% of genotyped infections. Risk factors for infection included male sex (P = 0.001), daycare attendance (P<0.001), having a household latrine (P = 0.04), childhood (P<0.001) and maternal soil-transmitted helminth (P = 0.029) infections, and exposures to donkeys (age interaction P = 0.034). G. lamblia was associated with increased risk of diarrhea (per episode, RR 1.03, 95% CI 1.01-1.06, P = 0.011) during the first 3 years of life and a transient impairment of weight (age interaction P = 0.017) and height-for-age (age interaction P = 0.025) trajectories between 1 and 4 years of age. There was no increased risk of either assemblage being associated with outcomes.

CONCLUSION

Our data show a relatively high edemicity of G. lamblia transmission during childhood in coastal Ecuador, and evidence that infection is associated with a transiently increased risk of diarrhea during the first 3 years of life and impairment of weight and height between 1 and 4 years.

Sexually transmitted infections and factors associated with risky sexual practices among female sex workers: A cross sectional study in a large Andean city

Background

There are limited published data on factors related to risky sexual practices (RSP) affecting sexually transmitted infections (STIs) among female sex workers (FSWs) in Ecuador.

Methods

Cross-sectional study of FSWs presenting for a consultation in a primary health care centre during 2017. A questionnaire was administered to collect information on RSP and potential risk factors including age, membership of an FSW association, self-report of previous STI diagnosis, previous treatment for suspected STI and temporary migration for sex work. Associations between RSP and potential risk factors were estimated by logistic regression. The proportion of STI was estimated from vaginal swabs by real-time PCR for four sexually transmitted pathogens (Neisseria gonorrhoeae, Trichomonas vaginalis, Chlamydia trachomatis, and Mycoplasma genitalium).

Results

Of 249 FSWs recruited, 22.5% had reported RSPs at least once during sex work. Among FSWs reporting unprotected vaginal sex in the previous three months, 25.5% had at least one other RSP type. 17.6% (95%CI 13.3–22.8) had at least one active STI. Prevalence of co-infections was 2.4% (95%CI 1.1–5.2). In multivariable analysis, RSP was associated with age (adjusted OR 1.06; 95%CI 1.02–1.10), membership of an FSWs association (aOR 3.51; 95%CI 1.60–7.72) and self-reported previous STI (aOR 3.43; 95%CI 1.28–9.17).

Conclusions

Among a population of female sex workers with high proportion of STIs, increasing age and belonging to an FSWs association was associated with a higher likelihood of engaging in RSP with clients. Engaging with FSWs organisations may reduce the burden of STI among sex workers.