Susan L. Hills

Control of scabies, skin sores and haematuria in children in the Solomon Islands: another role for ivermectin

OBJECTIVE To assess the effects of a 3-year programme aimed at controlling scabies on five small lagoon islands in the Solomon Islands by monitoring scabies, skin sores, streptococcal skin contamination, serology and haematuria in the island children. METHODS Control was achieved by treating almost all residents of each island once or twice within 2 weeks with ivermectin (160-250 microg/kg), except for children who weighed less than 15 kg and pregnant women, for whom 5% permethrin cream was used. Reintroduction of scabies was controlled by treating returning residents and visitors, whether or not they had evident scabies. FINDINGS Prevalence of scabies dropped from 25% to less than 1% (P < 0.001); prevalence of sores from 40% to 21% (P < 0.001); streptococcal contamination of the fingers in those with and without sores decreased significantly (P = 0.02 and 0.047, respectively) and anti-DNase B levels decreased (P = 0.002). Both the proportion of children with haematuria and its mean level fell (P = 0.002 and P < 0.001, respectively). No adverse effects of the treatments were seen. CONCLUSION The results show that ivermectin is an effective and practical agent in the control of scabies and that control reduces the occurrence of streptococcal skin disease and possible signs of renal damage in children. Integrating community-based control of scabies and streptococcal skin disease with planned programmes for controlling filariasis and intestinal nematodes could be both practical and produce great health benefits.

Japanese Encephalitis Surveillance and Immunization — Asia and Western Pacific Regions, 2016

Japanese encephalitis (JE) virus is the most important vaccine-preventable cause of encephalitis in the Asia-Pacific region. The World Health Organization (WHO) recommends integration of JE vaccination into national immunization schedules in all areas where the disease is a public health priority (1). This report updates a previous summary of JE surveillance and immunization programs in Asia and the Western Pacific in 2012 (2). Since 2012, funding for JE immunization has become available through the GAVI Alliance, three JE vaccines have been WHO-prequalified,* and an updated WHO JE vaccine position paper providing guidance on JE vaccines and vaccination strategies has been published (1). Data for this report were obtained from a survey of JE surveillance and immunization practices administered to health officials in countries with JE virus transmission risk, the 2015 WHO/United Nations Childrens Fund Joint Reporting Form on Immunization, notes and reports from JE meetings held during 2014-2016, published literature, and websites. In 2016, 22 (92%) of 24 countries with JE virus transmission risk conducted JE surveillance, an increase from 18 (75%) countries in 2012, and 12 (50%) countries had a JE immunization program, compared with 11 (46%) countries in 2012. Strengthened JE surveillance, continued commitment, and adequate resources for JE vaccination should help maintain progress toward prevention and control of JE.

Zika virus as a sexually transmitted pathogen

Purpose of review Zika virus has recently emerged from an obscure mosquito-borne pathogen to an international public health concern. It is the first viral agent newly demonstrated to cause birth defects in several decades, and it is the only arbovirus now known to be transmitted sexually. The purpose of this review is to provide an overview of current understanding of sexual transmission of Zika virus and its possible clinical and public health consequences. Recent findings Sexual transmission of Zika virus has been reported from at least 13 countries without simultaneous mosquito-borne transmission; it is undoubtedly also occurring in countries with active arthropod transmission. Most published cases involve transmission from symptomatically infected men to women partners. Nevertheless, transmission from a symptomatic man to another man, from a symptomatic woman to a man, and from an asymptomatic man to a woman has also been reported. Sexual transmission has occurred before symptom onset, during illness, and after resolution of the source partners symptoms. With the exception of a woman who developed symptomatic infection 44 days after onset of her husbands illness, nearly all instances reported to date have occurred within 20 days of the source partners illness. Zika virus RNA has been detected in semen, saliva, blood, urine, and vaginal and cervical secretions; the length of time during which RNA can be detected varies widely across different body fluids but is especially lengthy in semen. Although semen has been found to contain ZIKV RNA for more than 180 days after illness onset, only a small proportion of samples with detectable RNA yield replicative virus whenever cultured. Summary Public health agencies have promulgated interim recommendations to prevent sexual transmission of Zika virus; however, much remains unknown regarding the duration of contagiousness and risk factors for transmission. Given the risk for birth defects, the greatest concern is for transmission of the virus to women who are pregnant or attempting to become pregnant. To prevent sexual transmission in general, couples are advised to use condoms or not have sex for at least 6 months from the start of the male partners symptoms or the date he was diagnosed with Zika or after he has returned from an area with risk of ZIKV infection. Women who have symptomatic ZIKV infection or have traveled to an area of risk are advised to use condoms or avoid sex for 8 weeks from the start of the womans symptoms or the date she was diagnosed with Zika or after the woman returns from the area of risk.

Field evaluation of commercial immunoglobulin M antibody capture ELISA diagnostic tests for the detection of Japanese encephalitis virus infection among encephalitis patients in Nepal.

OBJECTIVES Japanese encephalitis (JE) is a devastating disease with high rates of death and disability that occurs particularly in resource-limited, rural regions of Asia. Simple, accurate and inexpensive diagnostics tests are vital for quantifying the burden of illness. This field study evaluated two commercial JE immunoglobulin M antibody capture (MAC) ELISA kits using samples from routine JE surveillance. METHODS Positive (n=132) and negative (n=218) sera were randomly selected from patient samples collected as part of JE surveillance in Nepal in 2005. Samples were tested in a national public health laboratory with commercial kits produced by XCyton and Inverness (Panbio). Results were compared with those of the research lab-based reference standard, the Armed Forces Research Institute of Medical Sciences JE MAC ELISA. RESULTS Positive and negative predictive values and 95% confidence intervals were 90% (82-95%) and 85% (79-89%) for Panbio1, 94% (88-98%) and 89% (87-93%) for Panbio2, and 84% (77-90%) and 96% (92-98%) for XCyton kits, respectively. Sensitivities of Panbio1, Panbio2, and XCyton kits were 71% (63-79%), 80% (72-87%), and 93% (88-97%); specificities were 95% (91-98%), 97% (94-99%), and 89% (85-93%), respectively. Overall percent agreement was 86% for Panbio1 and 91% for both Panbio2 and XCyton. CONCLUSIONS Both commercial kits had good predictive values when single serum samples from encephalitis cases were tested in a national laboratory. Either kit can be used in similar JE-endemic settings where co-transmission of dengue virus, a flavivirus which has strong cross-reactivity with JE, is limited. These results can inform decisions by countries and the World Health Organization laboratory networks on national-level use of these kits for JE surveillance.

Recognising and responding to outbreaks of hepatitis A associated with child day-care centres.

Objectives: To assess the appropriateness of a protocol for recognising and responding to outbreaks of hepatitis A in child day‐care centres and to determine if measles‐mumps‐rubella (MMR) vaccine was given too soon following the administration of normal human immunoglobulin (NIGH) to young children to control the outbreaks.

Ability To Serologically Confirm Recent Zika Virus Infection in Areas with Varying Past Incidence of Dengue Virus Infection in the United States and U.S. Territories in 2016

ABSTRACT Cross-reactivity within flavivirus antibody assays, produced by shared epitopes in the envelope proteins, can complicate the serological diagnosis of Zika virus (ZIKAV) infection. We assessed the utility of the plaque reduction neutralization test (PRNT) to confirm recent ZIKAV infections and rule out misleading positive immunoglobulin M (IgM) results in areas with various levels of past dengue virus (DENV) infection incidence. We reviewed PRNT results of sera collected for diagnosis of ZIKAV infection from 1 January through 31 August 2016 with positive ZIKAV IgM results, and ZIKAV and DENV PRNTs were performed. PRNT result interpretations included ZIKAV, unspecified flavivirus, DENV infection, or negative. For this analysis, ZIKAV IgM was considered false positive for samples interpreted as a DENV infection or negative. In U.S. states, 208 (27%) of 759 IgM-positive results were confirmed to be ZIKAV compared to 11 (21%) of 52 in the U.S. Virgin Islands (USVI), 15 (15%) of 103 in American Samoa, and 13 (11%) of 123 in Puerto Rico. In American Samoa and Puerto Rico, more than 80% of IgM-positive results were unspecified flavivirus infections. The false-positivity rate was 27% in U.S. states, 18% in the USVI, 2% in American Samoa, and 6% in Puerto Rico. In U.S. states, the PRNT provided a virus-specific diagnosis or ruled out infection in the majority of IgM-positive samples. Almost a third of ZIKAV IgM-positive results were not confirmed; therefore, providers and patients must understand that IgM results are preliminary. In territories with historically higher rates of DENV transmission, the PRNT usually could not differentiate between ZIKAV and DENV infections.

Effect of Aerial Insecticide Spraying on West Nile Virus Disease—North-Central Texas, 2012

During 2012, four north-central Texas counties experienced high West Nile virus (WNV) disease incidence. Aerial insecticide spraying was conducted in two counties. To evaluate the effect of spraying on WNV disease, we calculated incidence rate ratios (IRRs) in treated and untreated areas by comparing incidence before and after spraying; for unsprayed areas, before and after periods were defined by using dates from a corresponding sprayed area. In treated areas, WNV neuroinvasive disease incidence before and after spraying was 7.31/100,000 persons and 0.28/100,000 persons, respectively; the IRR was 26.42 (95% confidence interval [CI]: 12.42-56.20). In untreated areas, the before and after incidence was 4.80/100,000 persons and 0.45/100,000 persons, respectively; the IRR was 10.57 (95% CI: 6.11-18.28). The ratio of IRRs was 2.50 (95% CI: 0.98-6.35). Disease incidence decreased in both areas, but the relative change was greater in aerial-sprayed areas.