Knowledge, attitudes, and practices associated with frequent influenza vaccination among healthcare personnel in Peru, 2016─2018.

Introduction: Despite a government-subsidized vaccination program, healthcare personnel (HCP) influenza vaccination uptake remains low in Peru. Using three years of cross-sectional surveys and an additional five years of prior vaccination history of HCP in Peru, we explored HCP knowledge, attitudes, and practices (KAP) of influenza illness and its impact on vaccination frequency. Methods: In 2016, the Estudio Vacuna de Influenza Peru (VIP) cohort was initiated in Lima, Peru, which collected information about HCP KAP and influenza vaccination history from 2011─2018. HCP were classified by their 8-year influenza vaccination history as never (0 years), infrequently (1─4 years), or frequently (5─8 years) vaccinated. Logistic regression models were used to describe KAP associated with frequent compared to infrequent influenza vaccination, adjusted for each HCP's healthcare workplace, age, sex, preexisting medical conditions, occupation, and length of time providing direct patient care. Results: From 2016─2018, 5131 HCP were recruited and 3120 fully enrolled in VIP; 2782 consistently reported influenza vaccination status and became our analytic sample. From 2011─2018, 14.3% of HCP never, 61.4% infrequently, and 24.4% frequently received influenza vaccines. Compared to HCP who were infrequently vaccinated, frequently vaccinated HCP were more likely to believe they were susceptible to influenza (adjusted odds ratio [aOR]:1.49, 95% confidence interval [CI]:1.22─1.82), perceived vaccination to be effective (aOR:1.92, 95%CI:1.59─2.32), were knowledgeable about influenza and vaccination (aOR:1.37, 95%CI:1.06─1.77), and believed vaccination had emotional benefits like reduced regret or anger if they became ill with influenza (aOR:1.96, 95%CI:1.60─2.42). HCP who reported vaccination barriers like not having time or a convenient place to receive vaccines had reduced odds of frequent vaccination (aOR:0.74, 95%CI:0.61─0.89) compared to those without reported barriers. Conclusion: Few HCP frequently received influenza vaccines during an eight-year period. To increase HCP influenza vaccination in middle-income settings like Peru, campaigns could strengthen influenza risk perception, vaccine knowledge, and accessibility.

Effectiveness of Maternal Influenza Vaccination in Peru PRIME Cohort.

Background: Few studies have examined influenza vaccine effectiveness (VE) among women during pregnancy in middle-income countries. We used data from a prospective cohort of women who were pregnant in Peru to estimate effectiveness of the 2018 Southern Hemisphere influenza vaccine. Methods: Women at <28 weeks gestation were enrolled from 4 tertiary level hospitals in Lima, Peru at the start of the 2018 influenza season and followed until the end of their pregnancies. Participants had mid-turbinate nasal swabs collected and tested for influenza by reverse-transcription polymerase chain reaction (RT-PCR) with onset of ≥1 of myalgia, cough, runny nose or nasal congestion, sore throat, or difficulty breathing. Time-varying Cox proportional hazard regression models were used to estimate the risk of RT-PCR-confirmed influenza infection after adjusting for inverse probability treatment weight. Results: We followed 1896 women for a median of 127 days (interquartile range [IQR], 86-174). Participants had a median age of 29 years (IQR, 24-34). Among the 1896 women, 49% were vaccinated with the 2018 influenza vaccine and 1039 (55%) developed influenza-like illness, 76 (7%) of whom had RT-PCR-confirmed influenza. Incidence rates of RT-PCR-confirmed influenza were 36.6 and 15.3 per 100 000 person-days among women who were unvaccinated and vaccinated, respectively. Adjusted influenza VE was 22% (95% confidence interval, -64.1% to 62.9%). Conclusions: Participants vaccinated against influenza had more than 50% lower incidence of RT-PCR-confirmed influenza illness. Although the VE estimated through propensity weight-adjusted time-varying Cox regression did not reach statistical significance, our findings provide additional evidence about the value of maternal influenza vaccination in middle-income countries.

Severity of influenza illness by seasonal influenza vaccination status among hospitalised patients in four South American countries, 2013-19: a surveillance-based cohort study.

BACKGROUND: Although several studies have reported attenuated influenza illness following influenza vaccination, results have been inconsistent and have focused predominantly on adults in the USA. This study aimed to evaluate the severity of influenza illness by vaccination status in a broad range of influenza vaccine target groups across multiple South American countries. METHODS: We analysed data from four South American countries (Argentina, Brazil, Chile, and Paraguay) participating in REVELAC-i, a multicentre, test-negative design, vaccine effectiveness network including 41 sentinel hospitals. Individuals hospitalised at one of these centres with severe acute respiratory infection were tested for influenza by real-time RT-PCR, and were included in the analysis if they had complete information about their vaccination status and outcomes of their hospital stay. We used multivariable logistic regression weighted by inverse probability of vaccination and adjusted for antiviral use, duration of illness before admission, and calendar week, to calculate the adjusted odds ratios (aORs) of intensive care unit (ICU) admission and in-hospital death (and combinations of these outcomes) among influenza-positive patients by vaccination status for three target groups: young children (aged 6-24 months), adults (aged 18-64 years) with pre-existing health conditions, and older adults (aged ≥65 years). Survival curves were used to compare length of hospital stay by vaccination status in each target group. FINDINGS: 2747 patients hospitalised with PCR-confirmed influenza virus infection between Jan 1, 2013, and Dec 8, 2019, were included in the study: 649 children (70 [10·8%] fully vaccinated, 193 [29·7%] partially vaccinated) of whom 87 (13·4%) were admitted to ICU and 12 (1·8%) died in hospital; 520 adults with pre-existing medical conditions (118 [22·7%] vaccinated), of whom 139 (26·7%) were admitted to ICU and 55 (10·6%) died in hospital; and 1578 older adults (609 [38·6%] vaccinated), of whom 271 (17·2%) were admitted to ICU and 220 (13·9%) died in hospital. We observed earlier discharge among partially vaccinated children (adjusted hazard ratio 1·14 [95% CI 1·01-1·29]), fully vaccinated children (1·24 [1·04-1·47]), and vaccinated adults with pre-existing medical conditions (1·78 [1·18-2·69]) compared with their unvaccinated counterparts, but not among vaccinated older adults (0·82 [0·65-1·04]). Compared with unvaccinated individuals, lower odds of ICU admission were found for partially vaccinated children (aOR 0·64 [95% CI 0·44-0·92]) and fully vaccinated children (0·52 [0·28-0·98]), but not for adults with pre-existing conditions (1·25 [0·93-1·67]) or older adults (0·88 [0·72-1·08]). Lower odds of in-hospital death (0·62 [0·50-0·78]) were found in vaccinated versus unvaccinated older adults, with or without ICU admission, but did not differ significantly in partially vaccinated (1·35 [0·57-3·20]) or fully vaccinated young children (0·88 [0·16-4·82]) or adults with pre-existing medical conditions (1·09 [0·73-1·63]) compared with the respective unvaccinated patient groups. INTERPRETATION: Influenza vaccination was associated with illness attenuation among those hospitalised with influenza, although results differed by vaccine target group. These findings might suggest that attenuation of disease severity might be specific to certain target groups, seasons, or settings. FUNDING: US Centers for Disease Control and Prevention. TRANSLATIONS: For the Spanish and Portuguese translations of the abstract see Supplementary Materials section.

Effectiveness of Whole-Virus COVID-19 Vaccine among Healthcare Personnel, Lima, Peru.

In February 2021, Peru launched a COVID-19 vaccination campaign among healthcare personnel using an inactivated whole-virus vaccine. The manufacturer recommended 2 vaccine doses 21 days apart. We evaluated vaccine effectiveness among an existing multiyear influenza vaccine cohort at 2 hospitals in Lima. We analyzed data on 290 participants followed during February-May 2021. Participants completed a baseline questionnaire and provided weekly self-collected nasal swab samples; samples were tested by real-time reverse transcription PCR. Median participant follow-up was 2 (range 1-11) weeks. We performed multivariable logistic regression and adjusted for preselected characteristics. During the study, 25 (9%) participants tested SARS-CoV-2-positive. We estimated adjusted vaccine effectiveness at 95% (95% CI 70%-99%) among fully vaccinated participants and 100% (95% CI 88%-100%) among partially vaccinated participants. These data can inform the use and acceptance of inactivated whole-virus vaccine and support vaccination efforts in the region.

Influenza Incidence and Vaccine Effectiveness During the Southern Hemisphere Influenza Season - Chile, 2022.

The COVID-19 pandemic has affected influenza virus transmission, with historically low activity, atypical timing, or altered duration of influenza seasons during 2020-22 (1,2). Community mitigation measures implemented since 2020, including physical distancing and face mask use, have, in part, been credited for low influenza detections globally during the pandemic, compared with those during prepandemic seasons (1). Reduced population exposure to natural influenza infections during 2020-21 and relaxed community mitigation measures after introduction of COVID-19 vaccines could increase the possibility of severe influenza epidemics. Partners in Chile and the United States assessed Southern Hemisphere influenza activity and estimated age-group-specific rates of influenza-attributable hospitalizations and vaccine effectiveness (VE) in Chile in 2022. Chile's most recent influenza season began in January 2022, which was earlier than during prepandemic seasons and was associated predominantly with influenza A(H3N2) virus, clade 3C.2a1b.2a.2. The cumulative incidence of influenza-attributable pneumonia and influenza (P&I) hospitalizations was 5.1 per 100,000 person-years during 2022, which was higher than that during 2020-21 but lower than incidence during the 2017-19 influenza seasons. Adjusted VE against influenza A(H3N2)-associated hospitalization was 49%. These findings indicate that influenza activity continues to be disrupted after emergence of SARS-CoV-2 in 2020. Northern Hemisphere countries might benefit from preparing for an atypical influenza season, which could include early influenza activity with potentially severe disease during the 2022-23 season, especially in the absence of prevention measures, including vaccination. Health authorities should encourage all eligible persons to seek influenza vaccination and take precautions to reduce transmission of influenza (e.g., avoiding close contact with persons who are ill).

Incidence and seasonality of respiratory viruses among medically attended children with acute respiratory infections in an Ecuador birth cohort, 2011-2014.

BACKGROUND: Ecuador annually has handwashing and respiratory hygiene campaigns and seasonal influenza vaccination to prevent respiratory virus illnesses but has yet to quantify disease burden and determine epidemic timing. METHODS: To identify respiratory virus burden and assess months with epidemic activity, we followed a birth cohort in northwest Ecuador during 2011-2014. Mothers brought children to the study clinic for routine checkups at ages 1, 2, 3, 5, and 8 years or if children experienced any acute respiratory illness symptoms (e.g., cough, fever, or difficulty breathing); clinical care was provided free of charge. Those with medically attended acute respiratory infections (MAARIs) were tested for common respiratory viruses via real-time reverse-transcription polymerase chain reaction (rRT-PCR). RESULTS: In 2011, 2376 children aged 1-4 years (median 35 months) were enrolled in the respiratory cohort and monitored for 7017.5 child-years (cy). The incidence of respiratory syncytial virus (RSV) was 23.9 (95% CI 17.3-30.5), influenza 10.6 (2.4-18.8), adenoviruses 6.7 (4.6-28.0), parainfluenzas 5.0 (2.3-10.5), and rhinoviruses, bocaviruses, human metapneumoviruses, seasonal coronaviruses, and enteroviruses <3/100 cy among children aged 12-23 months and declined with age. Most (75%) influenza detections occurred April-September. CONCLUSION: Cohort children frequently had MAARIs, and while the incidence decreased rapidly among older children, more than one in five children aged 12-23 months tested positive for RSV, and one in 10 tested positive for influenza. Our findings suggest this substantial burden of influenza occurred more commonly during the winter Southern Hemisphere influenza season.

Influenza vaccine effectiveness within prospective cohorts of healthcare personnel in Israel and Peru 2016-2019.

BACKGROUND: There are limited data on influenza vaccine effectiveness (IVE) in preventing laboratory-confirmed influenza illness among healthcare personnel (HCP). METHODS: HCP with direct patient contact working full-time in hospitals were followed during three influenza seasons in Israel (2016-2017 to 2018-2019) and Peru (2016 to 2018). Trivalent influenza vaccines were available at all sites, except during 2018-2019 when Israel used quadrivalent vaccines; vaccination was documented by electronic medical records, vaccine registries, and/or self-report (for vaccinations outside the hospital). Twice-weekly active surveillance identified acute respiratory symptoms or febrile illness (ARFI); self-collected respiratory specimens were tested by real-time reverse transcription polymerase chain reaction (PCR) assay. IVE was 100 × 1-hazard ratio (adjusted for sex, age, occupation, and hospital). RESULTS: Among 5,489 HCP who contributed 10,041 person-seasons, influenza vaccination coverage was 47% in Israel and 32% in Peru. Of 3,056 ARFIs in Israel and 3,538 in Peru, A or B influenza virus infections were identified in 205 (7%) in Israel and 87 (2.5%) in Peru. IVE against all viruses across seasons was 1% (95% confidence interval [CI] = -30%, 25%) in Israel and 12% (95% CI = -61%, 52%) in Peru. CONCLUSION: Estimates of IVE were null using person-time models during six study seasons in Israel and Peru.

Incidence of influenza during pregnancy and association with pregnancy and perinatal outcomes in three middle-income countries: a multisite prospective longitudinal cohort study.

BACKGROUND: Influenza vaccination during pregnancy prevents influenza among women and their infants but remains underused among pregnant women. We aimed to quantify the risk of antenatal influenza and examine its association with perinatal outcomes. METHODS: We did a prospective cohort study in pregnant women in India, Peru, and Thailand. Before the 2017 and 2018 influenza seasons, we enrolled pregnant women aged 18 years or older with expected delivery dates 8 weeks or more after the season started. We contacted women twice weekly until the end of pregnancy to identify illnesses with symptoms of myalgia, cough, runny nose or nasal congestion, sore throat, or difficulty breathing and collected mid-turbinate nasal swabs from symptomatic women for influenza real-time RT-PCR testing. We assessed the association of antenatal influenza with preterm birth, late pregnancy loss (≥13 weeks gestation), small for gestational age (SGA), and birthweight of term singleton infants using Cox proportional hazards models or generalised linear models to adjust for potential confounders. FINDINGS: Between March 13, 2017, and Aug 3, 2018, we enrolled 11 277 women with a median age of 26 years (IQR 23-31) and gestational age of 19 weeks (14-24). 1474 (13%) received influenza vaccines. 310 participants (3%) had influenza (270 [87%] influenza A and 40 [13%] influenza B). Influenza incidences weighted by the population of women of childbearing age in each study country were 88·7 per 10 000 pregnant woman-months (95% CI 68·6 to 114·8) during the 2017 season and 69·6 per 10 000 pregnant woman-months (53·8 to 90·2) during the 2018 season. Antenatal influenza was not associated with preterm birth (adjusted hazard ratio [aHR] 1·4, 95% CI 0·9 to 2·0; p=0·096) or having an SGA infant (adjusted relative risk 1·0, 95% CI 0·8 to 1·3, p=0·97), but was associated with late pregnancy loss (aHR 10·7, 95% CI 4·3 to 27·0; p<0·0001) and reduction in mean birthweight of term, singleton infants (-55·3 g, 95% CI -109·3 to -1·4; p=0·0445). INTERPRETATION: Women had a 0·7-0·9% risk of influenza per month of pregnancy during the influenza season, and antenatal influenza was associated with increased risk for some adverse pregnancy outcomes. These findings support the added value of antenatal influenza vaccination to improve perinatal outcomes. FUNDING: US Centers for Disease Control and Prevention. TRANSLATIONS: For the Thai, Hindi, Marathi and Spanish translations of the abstract see Supplementary Materials section.

Prospective cohort study of influenza vaccine effectiveness among healthcare personnel in Lima, Peru: Estudio Vacuna de Influenza Peru, 2016-2018.

BACKGROUND: The Estudio Vacuna de Influenza Peru (VIP) cohort aims to describe the frequency of influenza virus infection, identify predictors of vaccine acceptance, examine the effects of repeated influenza vaccination on immunogenicity, and evaluate influenza vaccine effectiveness among HCP. METHODS: The VIP cohort prospectively followed HCP in Lima, Peru, during the 2016-2018 influenza seasons; a fourth year is ongoing. Participants contribute blood samples before and after the influenza season and after influenza vaccination (for vaccinees). Weekly surveillance is conducted to identify acute respiratory or febrile illnesses (ARFI). When an ARFI is identified, participants self-collect nasal swabs that are tested for influenza viruses by real-time reverse transcriptase-polymerase chain reaction. Influenza vaccination status and 5-year vaccination history are ascertained. We analyzed recruitment and enrollment results for 2016-2018 and surveillance participation for 2016-2017. RESULTS: In the first 3 years of the cohort, VIP successfully contacted 92% of potential participants, enrolled 76% of eligible HCP, and retained >90% of participants across years. About half of participants are medical assistants (54%), and most provide "hands-on" medical care (76%). Sixty-nine percent and 52% of participants completed surveillance for >70% of weeks in years 1 and 2, respectively. Fewer weeks of completed surveillance was associated with older age (≥50 years), being a medical assistant, self-rated health of fair or poor, and not receiving the influenza vaccine during the current season (P-values < .05). CONCLUSIONS: The VIP cohort provides an opportunity to address knowledge gaps about influenza virus infection, vaccination uptake, effectiveness and immunogenicity among HCP.

Heterogeneity in influenza seasonality and vaccine effectiveness in Australia, Chile, New Zealand and South Africa: early estimates of the 2019 influenza season.

We compared 2019 influenza seasonality and vaccine effectiveness (VE) in four southern hemisphere countries: Australia, Chile, New Zealand and South Africa. Influenza seasons differed in timing, duration, intensity and predominant circulating viruses. VE estimates were also heterogeneous, with all-ages point estimates ranging from 7-70% (I2: 33%) for A(H1N1)pdm09, 4-57% (I2: 49%) for A(H3N2) and 29-66% (I2: 0%) for B. Caution should be applied when attempting to use southern hemisphere data to predict the northern hemisphere influenza season.

Timing of respiratory syncytial virus and influenza epidemic activity in five regions of Argentina, 2007-2016.

BACKGROUND: Within-country differences in the timing of RSV and influenza epidemics have not been assessed in Argentina, the eighth largest country in the world by area. OBJECTIVE: We aimed to compare seasonality for RSV and influenza both nationally and in each of the five regions to inform Argentina's prevention and treatment guidelines. METHOD: The Argentine National Laboratories and Health Institutes Administration collected respiratory specimens from clinical practices, outbreak investigations, and respiratory virus surveillance in 2007-2016; these were tested using immunofluorescence or RT-PCR techniques. We calculated weekly percent positive (PP) and defined season onset as >2 consecutive weeks when PP exceeded the annual mean for the respective year and region. Median season measures (onset, offset and peak) and the established mean method were calculated for each virus. RESULTS: An annual median 59 396 specimens were tested for RSV and 60 931 for influenza; 21-29% tested positive for RSV and 2-7% for influenza. National RSV activity began in April; region-specific start weeks varied by 7 weeks. Duration of RSV activity did not vary widely by region (16-18 weeks in duration). National influenza activity started in June; region-specific start weeks varied by 3 weeks. Duration of influenza epidemic activity varied more by region than that of RSV (7-13 weeks in duration). CONCLUSION: In Argentina, RSV and influenza activity overlapped during the winter months. RSV season tended to begin prior to the influenza season, and showed more variation in start week by region. Influenza seasons tended to vary more in duration than RSV seasons.

Knowledge, attitudes and practices about influenza vaccination among pregnant women and healthcare providers serving pregnant women in Managua, Nicaragua.

BACKGROUND: Nicaragua implemented an influenza vaccination program for pregnant women with high-risk obstetric conditions in 2007. In 2014, the recommendation of influenza vaccination expanded to include all pregnant women. Given the expansion in the recommendation of vaccination, we evaluated knowledge, attitudes and practices of pregnant women and their healthcare providers towards influenza vaccination and its recommendation. METHODS: We conducted surveys among pregnant women and their healthcare providers from June to August 2016 at two hospitals and 140 health facilities in Managua. The questions were adapted from the U.S. national CDC influenza survey and related to knowledge, attitudes and practices about influenza vaccination and barriers to vaccination. We analyzed reasons for not receiving vaccination among pregnant women as well as receipt of vaccination recommendation and offer by their healthcare providers. RESULTS: Of 1,303 pregnant women enrolled, 42% (5 4 5) reported receiving influenza vaccination in the 2016 season. Of those who reported not receiving vaccination, 46% indicated barriers to vaccination. Pregnant women who were vaccinated were more likely to be aware of the recommendation for vaccination and the risks of influenza illness during pregnancy and to perceive the vaccine as safe and effective, compared to unvaccinated pregnant women (p-values < 0.001). Of the 619 health workers enrolled, over 89% recalled recommending influenza vaccination to all pregnant women, regardless of obstetric risk. Of the 1,223 women who had a prenatal visit between the start date of the influenza vaccination and the time of interview, 44% recalled receiving a recommendation for influenza vaccination and 43% were offered vaccination. Vaccination rates were higher for those receiving a recommendation and offer of vaccination compared with those who received neither (95% vs 5%, p-value < 0.001). CONCLUSION: Pregnant women in Managua had positive perceptions of influenza vaccine and were receptive to receiving influenza vaccination, especially after the offer and recommendation by their healthcare providers.

Association of influenza vaccination during pregnancy with birth outcomes in Nicaragua.

BACKGROUND: Studies have shown that influenza vaccination during pregnancy reduces the risk of influenza disease in pregnant women and their offspring. Some have proposed that maternal vaccination may also have beneficial effects on birth outcomes. In 2014, we conducted an observational study to test this hypothesis using data from two large hospitals in Managua, Nicaragua. METHODS: We conducted a retrospective cohort study to evaluate associations between influenza vaccination and birth outcomes. We carried out interviews and reviewed medical records post-partum to collect data on demographics, influenza vaccination during pregnancy, birth outcomes and other risk factors associated with adverse neonatal outcomes. We used influenza surveillance data to adjust for timing of influenza circulation. We assessed self-reports of influenza vaccination status by further reviewing medical records of those who self-reported but did not have readily available evidence of vaccination status. We performed multiple logistic regression (MLR) and propensity score matching (PSM). RESULTS: A total of 3268 women were included in the final analysis. Of these, 55% had received influenza vaccination in 2014. Overall, we did not observe statistically significant associations between influenza vaccination and birth outcomes after adjusting for risk factors, with either MLR or PSM. With PSM, after adjusting for risk factors, we observed protective associations between influenza vaccination in the second and third trimester and preterm birth (aOR: 0.87; 95% confidence interval (CI): 0.75-0.99 and aOR: 0.66; 95% CI: 0.45-0.96, respectively) and between influenza vaccination in the second trimester and low birth weight (aOR: 0.80; 95% CI: 0.64-0.97). CONCLUSIONS: We found evidence to support an association between influenza vaccination and birth outcomes by trimester of receipt with data from an urban population in Nicaragua. The study had significant selection and recall biases. Prospective studies are needed to minimize these biases.

Multistate Outbreak of Respiratory Infections Among Unaccompanied Children, June 2014-July 2014.

BACKGROUND: From January 2014-July 2014, more than 46 000 unaccompanied children (UC) from Central America crossed the US-Mexico border. In June-July, UC aged 9-17 years in 4 shelters and 1 processing center in 4 states were hospitalized with acute respiratory illness. We conducted a multistate investigation to interrupt disease transmission. METHODS: Medical charts were abstracted for hospitalized UC. Nonhospitalized UC with influenza-like illness were interviewed, and nasopharyngeal and oropharyngeal swabs were collected to detect respiratory pathogens. Nasopharyngeal swabs were used to assess pneumococcal colonization in symptomatic and asymptomatic UC. Pneumococcal blood isolates from hospitalized UC and nasopharyngeal isolates were characterized by serotyping and whole-genome sequencing. RESULTS: Among 15 hospitalized UC, 4 (44%) of 9 tested positive for influenza viruses, and 6 (43%) of 14 with blood cultures grew pneumococcus, all serotype 5. Among 48 nonhospitalized children with influenza-like illness, 1 or more respiratory pathogens were identified in 46 (96%). Among 774 nonhospitalized UC, 185 (24%) yielded pneumococcus, and 70 (38%) were serotype 5. UC transferring through the processing center were more likely to be colonized with serotype 5 (odds ratio, 3.8; 95% confidence interval, 2.1-6.9). Analysis of core pneumococcal genomes detected 2 related, yet independent, clusters. No pneumococcus cases were reported after pneumococcal and influenza immunization campaigns. CONCLUSIONS: This respiratory disease outbreak was due to multiple pathogens, including Streptococcus pneumoniae serotype 5 and influenza viruses. Pneumococcal and influenza vaccinations prevented further transmission. Future efforts to prevent similar outbreaks will benefit from use of both vaccines.

Factors associated with a successful expansion of influenza vaccination among pregnant women in Nicaragua.

BACKGROUND: Pregnant women are at risk of severe influenza disease and are a priority group for influenza vaccination programs. Nicaragua expanded recommendations to include influenza vaccination to all pregnant women in the municipality of Managua in 2013. METHODS: We carried out a survey among 1,807 pregnant women who delivered at public hospitals in the municipality of Managua to evaluate the uptake of influenza vaccination and factors associated with vaccination. RESULTS: We observed a high (71%) uptake of influenza vaccination among this population, with no differences observed by age, education or parity of the women. Having four antenatal visits and five or more visits were associated with receipt of influenza vaccination (AORs: 2.58; 95% CI: 1.15, 5.81, and 2.37; 95% CI: 1.12, 5.0, respectively). Also, receipt of influenza vaccination recommendation from a health care provider was positively associated with receipt of influenza vaccination (AOR: 14.22; 95% CI: 10.45, 19.33). CONCLUSIONS: The successful expansion of influenza vaccination among pregnant women in the municipality of Managua may be due to ready access to free medical care and health care providers' recommendation for vaccination at health care clinics that received influenza vaccine.

Reasons for low influenza vaccination coverage among adults in Puerto Rico, influenza season 2013-2014.

BACKGROUND: Influenza vaccination is recommended annually for all persons 6 months and older. Reports of increased influenza-related morbidity and mortality during the 2013-2014 influenza season raised concerns about low adult influenza immunization rates in Puerto Rico. In order to inform public health actions to increase vaccination rates, we surveyed adults in Puerto Rico regarding influenza vaccination-related attitudes and barriers. METHODS: A random-digit-dialing telephone survey (50% landline: 50% cellphone) regarding influenza vaccination, attitudes, practices and barriers was conducted November 19-25, 2013 among adults in Puerto Rico. Survey results were weighted to reflect sampling design and adjustments for non-response. RESULTS: Among 439 surveyed, 229 completed the survey with a 52% response rate. Respondents' median age was 55 years; 18% reported receiving 2013-2014 influenza vaccination. Among 180 unvaccinated respondents, 38% reported barriers associated with limited access to vaccination, 24% reported they did not want or need influenza vaccination, and 20% reported safety concerns. Vaccinated respondents were more likely to know if they were recommended for influenza vaccination, to report greater perceived risk of influenza illness, and to report being less concerned about influenza vaccine safety (p-value<0.05). Of the 175 respondents who saw a healthcare provider (HCP) since July 1, 2013, 38% reported their HCP recommended influenza vaccination and 17% were offered vaccination. Vaccination rates were higher among adults who received a recommendation and/or offer of influenza vaccination (43% vs. 14%; p-value<0.01). CONCLUSIONS: Failure of HCP to recommend and/or offer influenza vaccination and patient attitudes (low perceived risk of influenza virus infection) may have contributed to low vaccination rates during the 2013-2014 season. HCP and public health practitioners should strongly recommend influenza vaccination and provide vaccinations during clinical encounters or refer patients for vaccination.

Chikungunya cases identified through passive surveillance and household investigations--Puerto Rico, May 5-August 12, 2014.

Chikungunya and dengue are mosquito-borne, viral, acute febrile illnesses that can be difficult to distinguish clinically. Whereas dengue is endemic in many countries in the Caribbean and the Americas, the first locally acquired chikungunya case in the Western Hemisphere was reported from the Caribbean island of St. Martin in December 2013 and was soon followed by cases in many parts of the region. In January 2014, the Puerto Rico Department of Health (PRDH) and CDC initiated chikungunya surveillance by building on an existing passive dengue surveillance system. To assess the extent of chikungunya in Puerto Rico, the severity of illnesses, and the health care-seeking behaviors of residents, PRDH and CDC analyzed data from passive surveillance and investigations conducted around the households of laboratory-positive chikungunya patients. Passive surveillance indicated that the first locally acquired, laboratory-positive chikungunya case in Puerto Rico was in a patient with illness onset on May 5, 2014. By August 12, a total of 10,201 suspected chikungunya cases (282 per 100,000 residents) had been reported. Specimens from 2,910 suspected cases were tested, and 1,975 (68%) were positive for chikungunya virus (CHIKV) infection. Four deaths were reported. The household investigations found that, of 250 participants, 70 (28%) tested positive for current or recent CHIKV infection, including 59 (84%) who reported illness within the preceding 3 months. Of 25 laboratory-positive participants that sought medical care, five (20%) were diagnosed with chikungunya and two (8%) were reported to PRDH. These investigative efforts indicated that chikungunya cases were underrecognized and underreported, prompting PRDH to conduct information campaigns to increase knowledge of the disease among health care professionals and the public. PRDH and CDC recommended that health care providers manage suspected chikungunya cases as they do dengue because of the similarities in symptoms and increased risk for complications in dengue patients that are not appropriately managed. Residents of and travelers to the tropics can minimize their risk for both chikungunya and dengue by taking standard measures to avoid mosquito bites.

New insights in cysticercosis transmission.

Taenia solium infection causes severe neurological disease in humans. Even though infection and exposure to swine cysticercosis is scattered throughout endemic villages, location of the tapeworm only explains some of the nearby infections and is not related to location of seropositive pigs. Other players might be involved in cysticercosis transmission. In this study we hypothesize that pigs that carry nematodes specific to dung beetles are associated with cysticercosis infection and/or exposure. We carried out a cross-sectional study of six villages in an endemic region in northern Peru. We euthanized all pigs (326) in the villages and performed necropsies to diagnose cysticercosis. For each pig, we counted cysticerci; measured anti-cysticercus antibodies; identified intestinal nematodes; tabulated distance to nearest human tapeworm infection; and recorded age, sex, productive stage, and geographic reference. For the purpose of this paper, we defined cysticercosis infection as the presence of at least one cysticercus in pig muscles, and cysticercosis exposure as seropositivity to anti-cysticercus antibodies with the presence of 0-5 cysticerci. Compared to pigs without nematode infections, those pigs infected with the nematode Ascarops strongylina were significantly associated with the presence of cysticerci (OR: 4.30, 95%CI: 1.83-10.09). Similarly, pigs infected with the nematode Physocephalus sexalatus were more likely to have cysticercosis exposure (OR: 2.21, 95%CI: 1.50-3.28). In conclusion, our results suggest that there appears to be a strong positive association between the presence of nematodes and both cysticercosis infection and exposure in pigs. The role of dung beetles in cysticercosis dynamics should be further investigated.

Notes from the field: hospitalizations for respiratory disease among unaccompanied children from Central America - multiple States, June-July 2014.

During October 2013-June 2014, approximately 54,000 unaccompanied children, mostly from the Central American countries of El Salvador, Guatemala, and Honduras, were identified attempting entry into the United States from Mexico, exceeding numbers reported in previous years. Once identified in the United States, U.S. Customs and Border Protection, an agency of the U.S. Department of Homeland Security, processes the unaccompanied children and transfers them to the Office of Refugee Resettlement (ORR), an office of the Administration for Children and Families, U.S. Department of Health and Human Services. ORR cares for the children in shelters until they can be released to a sponsor, typically a parent or relative, who can care for the child while their immigration case is processed. In June 2014, in response to the increased number of unaccompanied children, U.S. Customs and Border Protection expanded operations to accommodate children at a processing center in Nogales, Arizona. ORR, together with the U.S. Department of Defense, opened additional large temporary shelters for the children at Lackland Air Force Base, Texas; U.S. Army Garrison Ft. Sill, Oklahoma; and Naval Base Ventura County, California.