Human body morphology, prevalence of nasopharyngeal potential bacterial pathogens, and immunocompetence handicap principal

The microbiome of the nasopharynx

The nasopharyngeal microbiome is a dynamic microbial interface of the aerodigestive tract, and a diagnostic window in the fight against respiratory infections and antimicrobial resistance. As its constituent bacteria, viruses and mycobacteria become better understood and sampling accuracy improves, diagnostics of the nasopharynx could guide more personalized care of infections of surrounding areas including the lungs, ears and sinuses. This review will summarize the current literature from a clinical perspective and highlight its growing importance in diagnostics and infectious disease management.

Do the Low WHRs and BMIs Judged Most Attractive Indicate Better Health?

It is widely claimed that in well-nourished populations, very low female waist-hip ratios (WHRs) together with low body mass indices (BMIs) are judged attractive by men because these features reliably indicate superior health and fertility. However, studies show that mortality rates are higher in women with low BMIs than in women with average BMIs and are inversely related to BMI in subsistence populations. Measures of current health in women of reproductive age have not been similarly studied. We analyze large U.S. samples of reproductive-age women and show that controlling for other factors known to affect health, those with low BMIs (<20), WHRs, or waist/stature ratios did not have better health than those with values in the middle range, and there was no relationship between subsequent health outcomes and BMI in early adulthood. Lower self-reported BMIs were linked to poorer health and an increased risk of infection. However, based on recent U.S. natality data, primiparas with lower BMIs had a lower risk of an operative delivery and of gestational hypertension. Beyond these two parity-restricted effects, relevant studies and new tests fail to support the view that women with the very low BMIs and WHRs consistently judged attractive are generally healthier than women with average values; significant correlations were consistently in the opposite direction.

Sex differences in the risk factors for Staphylococcus aureus throat carriage

BACKGROUND

Male gender and adiposity are considered to be risk factors for Staphylococcus aureus carriage. We tested whether colonization is related to free testosterone (fT) level and adiposity, measured with body mass index (BMI) and body fat percentage (BFP), in healthy adults.

METHODS

Blood sample and throat swabs were taken twice (at 4-week intervals) from healthy men and women aged 18-36 years. fT level, height, weight, and BFP were measured. Participants were classified as persistent carriers, intermittent carriers (excluded from the analyses), and noncarriers. The final sample was 152 participants: 85 men and 67 women.

RESULTS

BFP, but not BMI, correlated positively with S aureus colonization (P = .02) in men. BMI became a significant predictor of carriage only when comparing groups within and above norms (P = .04). There was no relationship for BMI nor BFP in women. Higher fT level was related to persistent carriage (P = .02) in women, there was no relationship for fT level in men.

CONCLUSION

Risk factors for S aureus carriage are sex dependent. Within-sex variation in colonization is related to fT level in women, whereas in men it is related to the amount of body fat.