Risk factors for susceptibility to varicella in newly arrived adult migrants in Canada

Surveillance and risk assessment of health screening for vaccine-preventable diseases among international students in Japan: A cross-sectional study in 2020

We conducted a cross-sectional study using a structured questionnaire in three major Japanese cities from August 03 to 24, 2020 to clarify the current situation of health checkups, including vaccine-preventable diseases (VPDs), among international students at Japanese universities (JUs) and Japanese language schools (JLSs). The total response rate was 36%: 69 JUs (31%) and 137 JLSs (39%). Over 90% of these institutions conducted chest X-ray screening for tuberculosis among their students, whereas only 24.6% of JUs and 15.3% of JLSs performed general blood tests for health screening. Only 14.5% and 2.2% of the JUs and JLSs, respectively, required the submission of vaccination or antibody certificates for admission. The difficulties in requesting vaccination certificates from international students are due to poor legal requirements and concerns about rising costs for schools. From 2017 to 2019, 183 international students, principally from East Asia and Southeast Asia, were infected with VPDs, particularly tuberculosis (99 cases) and varicella (71 cases). Whereas the majority of Japanese educational institutions screen international students for tuberculosis (TB) at admission, only a few institutions request proof of antibody testing relating to other VPDs or of vaccination. These findings will help formulate guidelines for checkups related to vaccination for international students required to protect the educational institutions in Japan from the spread of VPDs. In addition, providing multifaceted social support, including financial compensation for institutions and enhanced international students' health issues, would be helpful.

Concordance of self-reported varicella history and serology among adolescent and adult refugee patients at a primary care clinic in Toronto, Canada

BACKGROUND

Previous studies have found higher rates of varicella susceptibility among migrants from tropical regions. This study seeks to estimate the prevalence of varicella susceptibility in a cohort of newly arrived refugees and refugee claimants at a primary care clinic in Toronto and to compare patients' self-reported history of varicella infection with serologic test results.

METHODS

We conducted a retrospective chart review of 1888 refugee patients aged 13 years and older rostered at a specialized primary care clinic in Toronto from December 2011 to October 2017. Basic sociodemographic variables, self-reported varicella history, and varicella serologic results were examined.

RESULTS

Based on serologic testing, 8.5% of individuals were varicella non-immune, with highest rates of varicella susceptibility among adolescents aged 13-19 years (13.5%). All adults over age 60 were varicella immune on serology (n = 56). A positive self-reported history of varicella infection was strongly predictive of varicella immunity on serology (PPV 96.8%; 95% CI: 95.2-97.9). A self-reported history of no prior varicella infection did not correlate reliably with serologic test results (NPV 15.8%; 95% CI: 13.3-18.0). A substantial proportion of patients (34.1%) were unsure of their varicella history.

CONCLUSION

Identification and immunization of varicella susceptible refugee newcomers remains a health care priority. Self-reported history of varicella infection had mixed reliability as a predictor of varicella immunity.

Vaccine completion and infectious diseases screening in a cohort of adult refugees following resettlement in the U.S.: 2013-2015

BACKGROUND

Refugees are frequently not immune to vaccine-preventable infections. Adherence to consensus guidelines on vaccination and infectious diseases screening among refugees resettling in the U.S. is unknown. We sought to determine rates of vaccine completion and infectious diseases screening in refugees following resettlement.

METHODS

We conducted a retrospective cohort study of refugees resettling in a region in the U.S. using medical data from June 2013-April 2015. We determined the proportion of vaccine-eligible refugees vaccinated with measles-mumps-rubella (MMR), hepatitis A/B, tetanus, diphtheria, and acellular pertussis (Tdap), and human papillomavirus (HPV) following resettlement. We also determined the proportion of refugees who completed HIV and hepatitis C (HCV) screening.

RESULTS

One hundred and eleven subjects were included, primarily from Iraq (53%), Afghanistan (19%), and Eritrea (11%). Of the 84 subjects who were vaccine-eligible, 78 (93%) initiated and 42 (50%) completed vaccinations within one year of resettlement. Odds of completing vaccination were higher for men (OR: 2.38; 95%CI:1.02-5.71) and for subjects with English proficiency (OR: 3.70; 95%CI:1.04-17.49). Of the 78 subjects (70%) completing HIV screening, two (3%) were diagnosed with HIV. Nearly all subjects completed screening for HCV, and one had active infection.

CONCLUSION

While most refugees initiate vaccinations, only 50% completed vaccinations and 70% completed HIV screening within 1 year of resettlement. There is a need to emphasize vaccine completion and HIV screening in refugee patients following resettlement.

Epidemiology of varicella among immigrants and non-immigrants in Quebec, Canada, before and after the introduction of childhood varicella vaccination: a retrospective cohort study

BACKGROUND

Many immigrants are susceptible to varicella on arrival to Canada because of different transmission dynamics in their countries of origin and scarcity of vaccination. Universal childhood vaccination programmes decrease varicella incidence rates through herd immunity, but the accumulating number of susceptible adult immigrants could remain at risk for severe varicella. Our aim was to describe the epidemiology of varicella among immigrants and non-immigrants before and after childhood varicella vaccination.

METHODS

We did a population-based, retrospective cohort study of all varicella cases in Quebec, Canada, diagnosed between 1996 and 2014 in administrative health databases linked to immigration data. Cases of varicella met diagnostic codes in the International Classification of Diseases, Ninth and Tenth Revision Canadian modifications. Cases with a co-occurring zoster diagnostic code and immigrants from Australia, New Zealand, the USA, and western European countries were excluded. Vaccination periods included pre-vaccination (1996-98), private vaccination (1999-2005), and public vaccination (2006-14). Incidence rate and comparative rate ratios were estimated using census data.

FINDINGS

A total of 231 339 varicella cases diagnosed between Jan 1, 1996, and Dec 31, 2014, were linked to 1 115 696 immigrants who arrived between Jan 1, 1980, and Dec 31, 2014. 1444 herpes zoster cases and 1276 immigrants from Australia, western Europe, New Zealand, and the USA were excluded. Among 228 619 varicella cases, 13 315 (5·8%) occurred in immigrants. In pre-vaccination versus public vaccination periods, varicella incidence declined in immigrants by 87% (95% CI 86·6-87·9; 324·3 cases per 100 000 person-years to 40·9 cases per 100 000 person-years) and in non-immigrants by 93% (92·4-92·7; 484 cases per 100 000 person-years to 36 cases per 100 000 person-years). Mean age at diagnosis increased in both groups (15·1 vs 19·4 years in immigrants and 8·4 vs 12·0 years in non-immigrants). In the public vaccination period, immigrants younger than 50 years had higher varicella rates than non-immigrants, with relative risk ranging from 1·53 (95% CI 1·37-1·72) to 4·64 (3·90-5·53) with the highest risk in adolescents and young adults, and people from Latin America and the Caribbean (age-specific incidence rate ratio [aIRR]_I-NI pre-vaccination 2·19 and post-vaccination aIRR_I-NI6·07) and south Asia (aIRR_I-NI pre-vaccination 3·41 and aIRR_I-NI post-vaccination 4·46) and in childbearing women (15-40 years; IRR_I-NI 2·48).

INTERPRETATION

Immigrant adolescents, young adults, and women of childbearing age had higher age-standardised rates of varicella than non-immigrants, with increasing disparities following vaccine introduction. Immigrants younger than 50 years of age would benefit from targeted vaccination upon arrival to host countries.

FUNDING

The Canadian Institutes of Health Research and The Department of Medicine, Jewish General Hospital, Montreal, QC, Canada.

Infectious and dermatological diseases among arriving migrants on the Italian coasts

Background

Since 2008 Italy has been the destination of the 'central Mediterranean route', used by migrants to reach Europe. The aim of this study is to describe demographic characteristics and health problems of migrants at the time of arrival on the Italian coasts, focussing on dermatological and infectious diseases.

Methods

Cross-sectional study of data routinely collected (n = 6, 188) by the National Institute for Health Migration and Poverty (INMP) in the centres for migrants of Lampedusa and Trapani-Milo (2015-16). Logistic models were performed to identify factors associated with scabies, varicella and the occurrence of two or more not related diagnosis.

Results

The average age was 21.6 years; 83.5% of the patients were males. The most frequent countries of origin were Eritrea, Nigeria, and Somalia. The most frequent diagnosis was scabies (58% of patients), skin infections, pediculosis and dermatitis; respiratory infections and varicella were the most represented infectious diseases. The diagnosis of scabies was more probable among Somalis (OR: 11.60) and Eritreans (OR: 10.05); the diagnosis of varicella was more probable among Ghanaians (OR: 13.58) and Nigerians (OR: 9.79). Somalis (OR: 4.10) and Eritreans (OR: 3.32) were the patients more likely to receive two or more diagnosis.

Conclusions

The majority of the diseases affecting migrants is in most cases, related to the migration experience and is likely not to represent a major threat for public health. Up-to-date information regarding the burden of diseases is needed in order to identify the health needs of incoming migrants and to arrange the appropriate response in terms of health services provision.

Migration Medicine

Migration is increasing and practitioners need to be aware of the unique health needs of this population. The prevalence of infectious diseases among migrants varies and generally mirrors that of their countries of origin, but is modified by the circumstance of migration, the presence of pre-arrival screening programs and post arrival access to health care. To optimize the health of migrants practitioners; (1) should take all opportunities to screen migrants at risk for latent infections such as tuberculosis, chronic hepatitis B and C, HIV, strongyloidiasis, schistosomiasis and Chagas disease, (2) update routine vaccines in all age groups and, (3) be aware of "rare and tropical infections" related to migration and return travel.

Epidemic Varicella Zoster Virus among University Students, India

We investigated a yearlong varicella zoster virus outbreak in a highly susceptible young adult population at a large university in India. Outbreaks of varicella infection among adults are not well described in the literature. Infection control measures and vaccination policy for this age group and setting are needed.

Fatal varicella in immigrants from tropical countries: Case reports and forensic perspectives

The primary Varicella Zoster Virus (VZV) infection results in varicella, a generally benign, self-limiting disease in immunocompetent children. Despite the usual course a possible fatal evolution of the primary infection is observed predominantly in immunocompromised subjects and in adults, especially emigrating from tropical regions. Two cases of fatal varicella have been investigated and discussed. Death occurred in two patients over 40 years of age, coming from South Asia and receiving chronic immunosuppressive therapy. The forensic expert must be cautious and consider all clinical records in managing fatal varicella cases, bearing in mind risk factors and pre-existing conditions such as age, geographical provenance and pathological comorbidity, which may lead to a bad prognosis irrespective of therapies. Based on the severe and fatal course observed in the reported cases, an extension of the immunization program appears advisable for immigrants from tropical countries, especially before scheduled immunotherapy.

Serological Susceptibility to Varicella Among U.S. Immigration and Customs Enforcement Detainees

U.S. Immigration and Customs Enforcement (ICE) is responsible for detaining unauthorized aliens during immigration proceedings. During 2014 to 2015, adult ICE detainees at a California facility were invited to complete a survey concerning self-reported varicella history and risk factors. Participants underwent serological testing for varicella-zoster virus (VZV) IgG; susceptible individuals were offered varicella vaccination. Among 400 detainees with available serology results, 48 (12%) were susceptible to varicella. Self-reported varicella history was negatively associated with susceptibility (adjusted odds ratio = 0.16; 95% confidence interval [0.07, 0.35]). Among 196 detainees reporting a positive history, 95% had VZV IgG levels suggestive of varicella immunity. Among 44 susceptible detainees offered vaccination, 86% accepted. Given relatively high varicella susceptibility, targeted screening and vaccination among ICE detainees lacking a positive history might reduce varicella transmission risks.

Vaccination in newly arrived immigrants to the European Union

The challenge of assimilating millions of immigrants in the European region each year presents significant socioeconomic issues. Among them is the threat of vaccine preventable diseases (VPDs) disease transmission within immigrant groups and the broader population given the permeability of nation state borders. A total of 3.8 million people immigrated to the European Union (EU) in 2014, among those were 1.6 million non-EU nationals. While vaccines have markedly reduced the transmission of disease, clusters of under-vaccinated individuals potentiate the rapid transmission of once-eradicated or controlled diseases. Immigrants pose a special challenge to host country public health vaccination programmes. Wars in their native countries may have interrupted vaccination programmes, documentation may be unavailable or unreliable, and refugees may present with health issues due to poor sanitation and food during transit. Further, immigrants are often reticent to access health care in the destination country, or may face financial or language barriers. Thus, preventive health care needs may go unaddressed and the first contact with a clinician is for an emergency. Equitable access to acute and preventive health care and services, including immunizations irrespective of individual's immigration status, should be a priority for European region countries. Ensuring appropriate and timely vaccination for immigrants could be accomplished with a universal European region immunization schedule. Priority should be given to highly communicable VPDs such as measles, mumps, rubella, pertussis, diphtheria, varicella and polio.

Varicella outbreak in Sudanese refugees from Calais

We describe an outbreak of varicella in 31 Sudanese refugees (all except one were male, mean age: 26 ± 1), from the Calais migrant camp and sheltered in a French transit area. The attack rate was 39%. Adults are scantly immunized against varicella zoster virus in East Africa and may be exposed to epidemics once in France.

Health status of newly arrived refugees in Toronto, Ont: Part 1: infectious diseases

OBJECTIVE

To determine the prevalence of selected infectious diseases among newly arrived refugee patients and whether there is variation by key demographic factors.

DESIGN

Retrospective chart review.

SETTING

Primary care clinic for refugee patients in Toronto, Ont.

PARTICIPANTS

A total of 1063 refugee patients rostered at the clinic from December 2011 to June 2014.

MAIN OUTCOME MEASURES

Demographic information (age, sex, and region of birth); prevalence of HIV, hepatitis B, hepatitis C, Strongyloides, Schistosoma, intestinal parasites, gonorrhea, chlamydia, and syphilis infections; and varicella immune status.

RESULTS

The median age of patients was 29 years and 56% were female. Refugees were born in 87 different countries. Approximately 33% of patients were from Africa, 28% were from Europe, 14% were from the Eastern Mediterranean Region, 14% were from Asia, and 8% were from the Americas (excluding 4% born in Canada or the United States). The overall rate of HIV infection was 2%. The prevalence of hepatitis B infection was 4%, with a higher rate among refugees from Asia (12%, P < .001). Hepatitis B immunity was 39%, with higher rates among Asian refugees (64%, P < .001) and children younger than 5 years (68%, P < .001). The rate of hepatitis C infection was less than 1%. Strongyloides infection was found in 3% of tested patients, with higher rates among refugees from Africa (6%, P = .003). Schistosoma infection was identified in 15% of patients from Africa. Intestinal parasites were identified in 16% of patients who submitted stool samples. Approximately 8% of patients were varicella nonimmune, with higher rates in patients from the Americas (21%, P < .001).

CONCLUSION

This study highlights the importance of screening for infectious diseases among refugee patients to provide timely preventive and curative care. Our data also point to possible policy and clinical implications, such as targeted screening approaches and improved access to vaccinations and therapeutics.

Summary of the Statement on International Travellers Who Intend to Visit Friends and Relatives

BACKGROUND

Travellers intending to visit friends and relatives (VFRs) are a specific group of travellers who have been identified as having an increased risk of travel-related morbidity.

OBJECTIVE

To provide recommendations for risk reduction in international VFRs.

METHODS

Recommendations regarding VFRs were developed based on available travel medicine literature and CATMAT expert opinion. Specific travel-related risks, including infectious disease epidemiology and burden in this population, were reviewed and recommendations were provided to attempt to mitigate these risks. Previous CATMAT statements related to VFRs were referred to and reiterated.

RECOMMENDATIONS

Rates of travel-related illness in VFRs tend to be higher for many conditions. Disease-specific risk factors and recommendations are discussed throughout this Statement. CATMAT recommends that VFRs' vaccinations be up-to-date and they be counselled on the importance of various risk reduction activities such as the use of malaria prophylaxis, safe sex practices and injury prevention. Pre- and/or post-travel tuberculosis testing is indicated in certain situations.

CONCLUSION

The pre-travel health assessment is an important opportunity to address with VFRs issues regarding health beliefs, health behaviours, current health status and the possibility of pre-existing conditions. Discussions addressing the importance of adherence to health advice and potential challenges to achieving adherence may be necessary.