Ecological disturbance alters the adaptive benefits of social ties.

Extreme weather events radically alter ecosystems. When ecological damage persists, selective pressures on individuals can change, leading to phenotypic adjustments. For group-living animals, social relationships may be a mechanism enabling adaptation to ecosystem disturbance. Yet whether such events alter selection on sociality and whether group-living animals can, as a result, adaptively change their social relationships remain untested. We leveraged 10 years of data collected on rhesus macaques before and after a category 4 hurricane caused persistent deforestation, exacerbating monkeys' exposure to intense heat. In response, macaques demonstrated persistently increased tolerance and decreased aggression toward other monkeys, facilitating access to scarce shade critical for thermoregulation. Social tolerance predicted individual survival after the hurricane, but not before it, revealing a shift in the adaptive function of sociality.

Natural disaster alters the adaptive benefits of sociality in a primate.

Weather-related disasters can radically alter ecosystems. When disaster-driven ecological damage persists, the selective pressures exerted on individuals can change, eventually leading to phenotypic adjustments. For group-living animals, social relationships are believed to help individuals cope with environmental challenges and may be a critical mechanism enabling adaptation to ecosystems degraded by disasters. Yet, whether natural disasters alter selective pressures on patterns of social interactions and whether group-living animals can, as a result, adaptively change their social relationships remains untested. Here, we leveraged unique data collected on rhesus macaques from 5 years before to 5 years after a category 4 hurricane, leading to persistent deforestation which exacerbated monkeys' exposure to intense heat. In response, macaques increased tolerance for and decreased aggression toward other monkeys, facilitating access to scarce shade critical for thermoregulation. Social tolerance predicted individual survival for 5 years after the hurricane, but not before it, revealing a clear shift in the adaptive function of social relationships in this population. We demonstrate that an extreme climatic event altered selection on sociality and triggered substantial and persistent changes in the social structure of a primate species. Our findings unveil the function and adaptive flexibility of social relationships in degraded ecosystems and identify natural disasters as potential evolutionary drivers of sociality. One-Sentence Summary: Testard et al. show that a natural disaster altered selection on sociality in group-living primates triggering persistent changes in their social structure.

Risk behaviour and STD acquisition in genitourinary clinic attenders who have travelled.

OBJECTIVE: To investigate the travel history of clients presenting at a genitourinary medicine (GUM) clinic in order to assess the contribution made by sexual partnerships abroad to STD transmission in the UK. SUBJECTS: 386 old and new clients who attended during a 3-month period and who had travelled abroad in the 3 months preceding their visit. METHODS: All participating clients self-completed a confidential questionnaire, the results of which were then linked to their clinical diagnosis (if any). RESULTS: 25% of participants reported a new sexual partner during their most recent trip abroad. In comparison to those not reporting a new partner, they were more likely to be male, travelling alone, to have visited the clinic previously and to have no regular sexual partner. Two-thirds reported never or inconsistently using condoms with these new partners. A total of 11.6% of the STDs diagnosed in the study participants may have been acquired abroad. CONCLUSION: We have found a high rate of new sexual relationships reported by attendees at our GUM clinic, and a low rate of reported condom use. With high HIV incidence rates in many tourist regions, the need for further studies to establish the true extent of imported STDs in the UK is a priority, and primary prevention campaigns to inform travellers are of paramount importance.

Risk behaviour and HIV prevalence in international travellers.

OBJECTIVE: To assess risk factors for infection and to determine HIV prevalence in a sample of international travellers. DESIGN: A cross-sectional survey of new patients attending a hospital outpatient clinic, and self-completion of an anonymous questionnaire on sexual behaviour prior to and during travel. Urine samples were tested for the presence of antibodies to HIV. SETTING: The Hospital for Tropical Diseases, London, UK. SUBJECTS: All new patients over a 6-month period. RESULTS: Of 782 people approached, 757 (97%) agreed to participate: 141 (18.6%) had had new sexual partners during their most recent trip abroad. Almost two-thirds of those having sex abroad did not use condoms on every occasion with a new partner, and 5.7% contracted a sexually transmitted disease (STD) during their most recent trip; 26% of men from World Health Organization Pattern I countries who had new sexual partners abroad paid for sex. Sixteen out of 731 (2.2%) participants were HIV-antibody-positive. HIV positivity was associated with being born in east, central or southern Africa, having symptoms of an STD since arriving in the United Kingdom and being treated for an STD since arrival. CONCLUSION: The rates of unsafe sex and payment for sex abroad reported by these international travellers indicate the potential for contracting and transmitting STD, including HIV, in both their foreign and domestic sexual partnerships. With the increasing HIV incidence in Asia (the most common destination for UK travellers after sub-Saharan Africa), the number of cases of HIV contracted abroad may rise in the future.

Patterns of hospital care for patients with HIV infection and AIDS.

OBJECTIVE: The aims were to describe the use of inpatient resources by patients with HIV infection and patients with AIDS; to examine trends in service use over time; and to provide data for planners concerned with service provision for HIV infection. SETTING: An inner London health district reporting 9% of AIDS cases nationally. DESIGN: Data on survival times and inpatient and day care use of resources were derived from existing patient records or collected prospectively between 1983 (when the first case of AIDS was diagnosed in the district) and 31 March 1990. SUBJECTS: A total of 488 HIV positive patients of whom 396 had been diagnosed as having AIDS were studied. MEASUREMENTS AND MAIN RESULTS: Inpatient days consumed per annum; trends in the number of bed days per person year with AIDS; the lifetime inpatient use per AIDS patient; and the influence of survival on service use estimates were determined. Altogether 16.4% of a total 17,785 hospital inpatient days were attributable to HIV positive patients who did not fulfil the criteria for AIDS. For patients with AIDS, there was an initial increase in the intensity of inpatient use in 1987 when a dedicated HIV ward was opened. After 1988, however, inpatient use fell to 30.8 bed days per person year with AIDS. Patients diagnosed after April 1987 had noticeably longer survival times than those diagnosed earlier (a median of 17-18 months compared with a median of 10-11 months). From 214 lifetime service use records, it was estimated that patients with short survival (less than six months) would consume 36 days of inpatient care, while those expected to survive longer would consume approximately twice that number of days, irrespective of how much longer they survived. CONCLUSIONS: The data indicate less intensive use of inpatient care by AIDS patients over time, and hence the apparent ability to manage an increasing AIDS patient workload without a comparable increase in occupied bed days. Increases in the size of that workload and changes in the survival profile of patients, together with a relatively constant rate of service demand by longer survivors, however, will continue to place increasing strains on finite inpatient resources. Further research is needed to establish the extent to which the greater use of outpatient and community services can offset this.

Auditing AIDS reporting. Experience from a central London district 1982-1991.

OBJECTIVE: To evaluate completeness of reporting of cases of AIDS to the Communicable Disease Surveillance Centre (CDSC) between 1982-1991. SETTING: Southside of the Bloomsbury and Islington District Health Authority. DESIGN: Reconciliation exercise with CDSC of cases reported with those known to have received treatment in the district from 1982 to March 1990. Case note review of unreported cases and follow-up at March 1991. MAIN OUTCOME MEASURES: Delayed and non-reporting of cases. RESULTS: Cumulatively 13% (46/351) of patients whose initial AIDS illness was diagnosed in the District remained unreported by March 1991. Non-reporting increased from 9% (2/23) of cases diagnosed prior to 1985 to 28% (26/92) of cases diagnosed between 1989 and 1990. After September 1987 the proportion of patients with a diagnosis of Pneumocystis carinii pneumonia or Kaposi's sarcoma was significantly higher in the reported group than in the non-reported group: 78% (124/158) v 51% (24/49) p < 0.001. Nine of 19 (47%) cases of AIDS transferring their care into the district had not been reported by their previous District Health Authority. CONCLUSIONS: Within the district non-reporting of cases of AIDS has risen over time as the numbers of patients treated has increased. The physician must be aware of the full AIDS case definition for surveillance purposes and the implications of non-reporting for the allocation of special "ring-fenced" resources for AIDS care. Adequate investment in information and reporting systems would seem essential.