Effectiveness of Nirsevimab Immunoprophylaxis Administered at Birth to Prevent Infant Hospitalisation for Respiratory Syncytial Virus Infection: A Population-Based Cohort Study

Respiratory syncytial virus (RSV) infection is a frequent cause of hospitalisation in the first few months of life; however, this risk rapidly decreases with age. Nirsevimab immunoprophylaxis was approved in the European Union for the prevention of RSV-associated lower respiratory tract disease in infants during their first RSV season. We evaluated the effectiveness of nirsevimab in preventing hospitalisations for confirmed RSV infection and the impact of a strategy of immunisation at birth. A population-based cohort study was performed in Navarre, Spain, where nirsevimab was offered at birth to all children born from October to December 2023. Cox regression was used to estimate the hazard ratio of hospitalisation for PCR-confirmed RSV infection between infants who received and did not receive nirsevimab. Of 1177 infants studied, 1083 (92.0%) received nirsevimab. The risk of hospitalisation for RSV was 8.5% (8/94) among non-immunised infants versus 0.7% (8/1083) in those that were immunised. The estimated effectiveness of nirsevimab was 88.7% (95% confidence interval, 69.6-95.8). Immunisation at birth of infants born between October and December 2023 prevented one hospitalisation for every 15.3 immunised infants. Immunisation of children born from September to January might prevent 77.5% of preventable hospitalisations for RSV in infants born in 2023-2024. These results support the recommendation of nirsevimab immunisation at birth to children born during the RSV epidemic or in the months immediately before to prevent severe RSV infections and alleviate the overload of paediatric hospital resources.

Effectiveness of one and two doses of acellular pertussis vaccines against laboratory-confirmed pertussis requiring hospitalisation in infants: Results of the PERTINENT sentinel surveillance system in six EU/EEA countries, December 2015 - December 2019

BACKGROUND

Monitoring effectiveness of pertussis vaccines is necessary to adapt vaccination strategies. PERTINENT, Pertussis in Infants European Network, is an active sentinel surveillance system implemented in 35 hospitals across six EU/EEA countries. We aim to measure pertussis vaccines effectiveness (VE) by dose against hospitalisation in infants aged <1 year.

METHODS

From December 2015 to December 2019, participating hospitals recruited all infants with pertussis-like symptoms. Cases were vaccine-eligible infants testing positive for Bordetella pertussis by PCR or culture; controls were those testing negative to all Bordetella spp. For each vaccine dose, we defined an infant as vaccinated if she/he received the corresponding dose >14 days before symptoms. Unvaccinated were those who did not receive any dose. We calculated (one-stage model) pooled VE as 100*(1-odds ratio of vaccination) adjusted for country, onset date (in 3-month categories) and age-group (when sample allowed it).

RESULTS

Of 1,393 infants eligible for vaccination, we included 259 cases and 746 controls. Median age was 16 weeks for cases and 19 weeks for controls (p < 0.001). Median birth weight and gestational age were 3,235 g and week 39 for cases, 3,113 g and week 39 for controls. Among cases, 119 (46 %) were vaccinated: 74 with one dose, 37 two doses, 8 three doses. Among controls, 469 (63 %) were vaccinated: 233 with one dose, 206 two doses, 30 three doses. Adjusted VE after at least one dose was 59 % (95 %CI: 36-73). Adjusted VE was 48 % (95 %CI: 5-71) for dose one (416 eligible infants) and 76 % (95 %CI: 43-90) for dose two (258 eligible infants). Only 42 infants were eligible for the third dose.

CONCLUSIONS

Our results suggest moderate one-dose and two-dose VE in infants. Larger sample size would allow more precise estimates for dose one, two and three.

Prevalence of Respiratory Viral Infections in Deceased Persons during the COVID-19 Pandemic Season 2021-2022: A Population-Based Observational Study

Although the omicron variant of SARS-CoV-2 circulated intensely during the 2021-2022 season, many patients with severe acute respiratory disease tested negative for COVID-19. The aim of this study was to assess the presence of different respiratory viruses in deceased persons. The proportion of deceased persons with respiratory viral infections in the 2021-2022 season in Navarre, Spain, was estimated considering all deaths caused by confirmed COVID-19 according to the epidemiological surveillance and the results of multiplex PCR tests for respiratory viruses performed in a sample of deceased persons with a cause of death other than COVID-19. Of 3578 deaths, 324 (9.1%) were initially reported as caused by pre-mortem confirmed COVID-19. A sample of 242 persons who died by causes other than COVID-19 were tested post-mortem; 64 (26.4%) of them were positive for any respiratory virus: 11.2% for SARS-CoV-2, 5.8% for rhinovirus, 3.7% for human coronavirus, 2.5% for metapneumovirus, 1.7% for respiratory syncytial virus, 1.7% for parainfluenza, 1.2% for influenza, and less than 1% each for adenovirus and bocavirus. Combining both approaches, we estimated that 34.4% of all deceased persons during the study period had a respiratory viral infection and 19.2% had SARS-CoV-2. Only 33.3% (9/27) of SARS-CoV-2 and 5.0% (2/40) of other viruses detected post-mortem had previously been confirmed pre-mortem. In a period with very intense circulation of SARS-CoV-2 during the pandemic, other respiratory viruses were also frequently present in deceased persons. Some SARS-CoV-2 infections and most other viral infections were not diagnosed pre-mortem. Several respiratory viruses may contribute to excess mortality in winter.

Hospitalisations and Deaths Averted by COVID-19 Vaccination in Navarre, Spain, 2021-2022

In 2021-2022, most of the Spanish population received COVID-19 vaccines and a high proportion of them had SARS-CoV-2 infection. We estimated the rate of hospitalisations and deaths that were averted by risk reduction among vaccinated COVID-19 cases. Hospitalisations and deaths were analysed among COVID-19 cases confirmed in 2021 and 2022 in Navarre, Spain. To calculate the number of prevented outcomes by sex, age, comorbidities, and semester, the difference in the risk of each outcome between unvaccinated and vaccinated cases was multiplied by the number of vaccinated cases. COVID-19 vaccination coverage with any dose reached 88%, 86% with full vaccination, and 56% with a booster dose. The cumulative rates per 1000 inhabitants were 382 COVID-19 confirmed cases, 6.70 hospitalisations, and 1.15 deaths from COVID-19. The estimated rates of prevented events by vaccination were 16.33 hospitalisations and 3.39 deaths per 1000 inhabitants, which was 70.9% and 74.7% of expected events without vaccination, respectively. People aged 80 years and older or with major chronic conditions accounted for the majority of hospitalizations and deaths prevented by COVID-19 vaccination. One hospitalisation and death due to COVID-19 were averted for every 53 and 258 people vaccinated, respectively. The high COVID-19 vaccine effect in reducing the risk of severe outcomes and the high vaccination coverage in risk populations prevented three out of four hospitalisations and deaths due to COVID-19 during a period of intense circulation of SARS-CoV-2.

Influenza Vaccine Effectiveness in Preventing Laboratory-Confirmed Influenza Cases and Hospitalizations in Navarre, Spain, 2022-2023

We estimated influenza vaccine effectiveness (IVE) in preventing outpatient and hospitalized cases in the 2022-2023 season. A test-negative design included a representative sample of outpatients and all hospitalized patients with influenza-like illness (ILI) from October 2022 to May 2023 in Navarre, Spain. ILI patients were tested by PCR for influenza virus. Influenza vaccination status was compared between confirmed influenza cases and test-negative controls. Among 3321 ILI patients tested, IVE to prevent influenza cases was 34% (95% confidence interval (CI): 16 to 48) overall, 85% (95%CI: 63 to 94) against influenza B, and 28% (95%CI: 3 to 46) against A(H3N2). Among 558 outpatients, 222 (40%) were confirmed for influenza: 55% A(H3N2), 11% A(H1N1), and 31% B. Overall, IVE to prevent outpatient cases was 48% (95%CI: 8 to 70), 88% (95%CI: 3 to 98) against influenza B, and 50% (95%CI: -4 to 76) against A(H3N2). Of 2763 hospitalized patients, 349 (13%) were positive for influenza: 64% A(H3N2), 17% A(H1N1), and 8% B. IVE to prevent hospitalization was 24% (95%CI: -1 to 42) overall, 82% (95%CI: 49 to 93) against influenza B, and 16% (95%CI: -17 to 40) against A(H3N2). No IVE was observed in preventing influenza A(H1N1). IVE was high to prevent influenza B, moderate against A(H3N2) and null against A(H1N1). A lower proportion of influenza B cases may explain the smaller IVE in hospitalized patients than in outpatients. The null IVE against A(H1N1) was consistent with the observed antigenic drift and supports the new composition of the 2023-2024 influenza vaccine.

Effect of COVID-19 vaccination on the SARS-CoV-2 transmission among social and household close contacts: A cohort study

BACKGROUND

COVID-19 vaccination was expected to reduce SARS-CoV-2 transmission, but the relevance of this effect remains unclear. We aimed to estimate the effectiveness of COVID-19 vaccination of the index cases and their close contacts in reducing the probability of SARS-CoV-2 transmission.

METHODS

Transmission of SARS-CoV-2 infection was evaluated in two cohorts of adult close contacts of COVID-19 confirmed cases (social and household settings) by COVID-19 vaccination status of the index case and the close contact, from April to November 2021 in Navarre, Spain. The effects of vaccination of the index case and the close contact were estimated as (1-adjusted relative risk) × 100%.

RESULTS

Among 19,631 social contacts, 3257 (17%) were confirmed with SARS-CoV-2. COVID-19 vaccination of the index case reduced infectiousness by 44% (95% CI, 27-57%), vaccination of the close contact reduced susceptibility by 69% (95% CI, 65-73%), and vaccination of both reduced transmissibility by 74% (95% CI, 70-78%) in social settings, suggesting some synergy of effects. Among 20,708 household contacts, 6269 (30%) were infected, and vaccine effectiveness estimates were 13% (95% CI, -5% to 28%), 61% (95% CI, 58-64%), and 52% (95% CI, 47-56%), respectively. These estimates were lower in older people and had not relevant differences between the Alpha (April-June) and Delta (July-November) variant periods.

CONCLUSIONS

COVID-19 vaccination reduces infectiousness and susceptibility; however, these effects are insufficient for complete control of SARS-CoV-2 transmission, especially in older people and household setting. Relaxation of preventive behaviors after vaccination may counteract part of the vaccine effect on transmission.

Risk reduction of hospitalisation and severe disease in vaccinated COVID-19 cases during the SARS-CoV-2 variant Omicron BA.1-predominant period, Navarre, Spain, January to March 2022

BackgroundAs COVID-19 vaccine effectiveness against SARS-CoV-2 infection was lower for cases of the Omicron vs the Delta variant, understanding the effect of vaccination in reducing risk of hospitalisation and severe disease among COVID-19 cases is crucial.AimTo evaluate risk reduction of hospitalisation and severe disease in vaccinated COVID-19 cases during the Omicron BA.1-predominant period in Navarre, Spain.MethodsA case-to-case comparison included COVID-19 epidemiological surveillance data in adults ≥ 18 years from 3 January-20 March 2022. COVID-19 vaccination status was compared between hospitalised and non-hospitalised cases, and between severe (intensive care unit admission or death) and non-severe cases using logistic regression models.ResultsAmong 58,952 COVID-19 cases, 565 (1.0%) were hospitalised and 156 (0.3%) were severe. The risk of hospitalisation was reduced within the first 6 months after full COVID-19 vaccination (complete primary series) (adjusted odds ratio (aOR): 0.06; 95% CI: 0.04-0.09) and after 6 months (aOR: 0.16; 95% CI: 0.12-0.21; p_comparison < 0.001), as well as after a booster dose (aOR: 0.06: 95% CI: 0.04-0.07). Similarly, the risk of severe disease was reduced (aOR: 0.13, 0.18, and 0.06, respectively). Compared with cases fully vaccinated 6 months or more before a positive test, those who had received a booster dose had lower risk of hospitalisation (aOR: 0.38; 95% CI: 0.28-0.52) and severe disease (aOR: 0.38; 95% CI: 0.21-0.68).ConclusionsFull COVID-19 vaccination greatly reduced the risk of hospitalisation and severe outcomes in COVID-19 cases with the Omicron variant, and a booster dose improved this effect in people aged over 65 years.

Comparison of the Risk of Hospitalization and Severe Disease Among Co-circulating Severe Acute Respiratory Syndrome Coronavirus 2 Variants

BACKGROUND

We compare the risk of coronavirus disease 2019 (COVID-19) outcomes among co-circulating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants between January 2021 and May 2022 in Navarra, Spain.

METHODS

We compared the frequency of hospitalization and severe disease (intensive care unit admission or death) due to COVID-19 among the co-circulating variants. Variants analyzed were nonvariants of concern (non-VOCs), Alpha, Delta, Omicron BA.1, and Omicron BA.2. Logistic regression models were used to estimate adjusted odds ratio (aOR).

RESULTS

The Alpha variant had a higher risk of hospitalization (aOR, 1.86 [95 confidence interval {CI}, 1.282.71]) and severe disease (aOR, 2.40 [95 CI, 1.314.40]) than non-VOCs. The Delta variant did not show a significantly different risk of hospitalization (aOR, 0.73 [95 CI, .401.30]) and severe disease (aOR, 3.04 [95 CI, .5716.22]) compared to the Alpha variant. The Omicron BA.1 significantly reduced both risks relative to the Delta variant (aORs, 0.28 [95 CI, .16.47] and 0.23 [95 CI, .12.46], respectively). The Omicron BA.2 reduced the risk of hospitalization compared to BA.1 (aOR, 0.52 [95 CI, .29.95]).

CONCLUSIONS

The Alpha and Delta variants showed an increased risk of hospitalization and severe disease, which decreased considerably with the Omicron BA.1 and BA.2. Surveillance of variants can lead to important differences in severity.

Seroprevalence of antibodies against SARS-CoV-2 and risk of COVID-19 in Navarre, Spain, May to July 2022

In Navarre, Spain, in May 2022, the seroprevalence of anti-nucleocapsid (N) and anti-spike (S) antibodies of SARS-CoV-2 was 58.9% and 92.7%, respectively. The incidence of confirmed COVID-19 thereafter through July was lower in people with anti-N antibodies (adjusted odds ratio (aOR) = 0.08; 95% confidence interval (CI): 0.05-0.13) but not with anti-S antibodies (aOR = 1.06; 95% CI: 0.47-2.38). Hybrid immunity, including anti-N antibodies induced by natural exposure to SARS-CoV-2, seems essential in preventing Omicron COVID-19 cases.

Effectiveness of influenza vaccination in preventing influenza in primary care, Navarre, Spain, 2021/22

Compared with individuals unvaccinated in the current and three previous influenza seasons, in 2021/22, influenza vaccine effectiveness at primary care level was 37% (95% CI: 16 to 52) for current season vaccination, regardless of previous doses, and 35% (95% CI: −3 to 45) for only previous seasons vaccination. Against influenza A(H3N2), estimates were 39% (95% CI: 16 to 55) and 24% (95% CI: −8 to 47) suggesting moderate effectiveness of current season vaccination and possible remaining effect of prior vaccinations.

Product-specific COVID-19 vaccine effectiveness against secondary infection in close contacts, Navarre, Spain, April to August 2021

COVID-19 vaccine effectiveness by product (two doses Comirnaty, Spikevax or Vaxzevria and one of Janssen), against infection ranged from 50% (95% CI: 42 to 57) for Janssen to 86% (70 to 93) for Vaxzevria-Comirnaty combination; among ≥ 60 year-olds, from 17% (−26 to 45) for Janssen to 68% (48 to 80) for Spikevax; and against hospitalisation from 74% (43 to 88) for Janssen to > 90% for other products. Two doses of vaccine were highly effective against hospitalisation, but suboptimal for infection control.

Simple models to include influenza vaccination history when evaluating the effect of influenza vaccination

Background

Most reports of influenza vaccine effectiveness consider current-season vaccination only.

Aim

We evaluated a method to estimate the effect of influenza vaccinations (EIV) considering vaccination history.

Methods

We used a test-negative design with well-documented vaccination history to evaluate the average EIV over eight influenza seasons (2011/12–2018/19; n = 10,356). Modifying effect was considered as difference in effects of vaccination in current and previous seasons and current-season vaccination only. We also explored differences between current-season estimates excluding from the reference category people vaccinated in any of the five previous seasons and estimates without this exclusion or only for one or three previous seasons.

Results

The EIV was 50%, 45% and 38% in people vaccinated in the current season who had previously received none, one to two and three to five doses, respectively, and it was 30% and 43% for one to two and three to five prior doses only. Vaccination in at least three previous seasons reduced the effect of current-season vaccination by 12 percentage points overall, 31 among outpatients, 22 in 9–65 year-olds, and 23 against influenza B. Including people vaccinated in previous seasons only in the unvaccinated category underestimated EIV by 9 percentage points on average (31% vs 40%). Estimates considering vaccination of three or five previous seasons were similar.

Conclusions

Vaccine effectiveness studies should consider influenza vaccination in previous seasons, as it can retain effect and is often an effect modifier. Vaccination status in three categories (current season, previous seasons only, unvaccinated) reflects the whole EIV.

Effect of influenza vaccination in patients with asthma

BACKGROUND:

Although annual influenza vaccination is recommended for persons with asthma, its effectiveness in this patient population is not well described. We evaluated the effect of influenza vaccination in the current and previous seasons in preventing influenza among people with asthma.

METHODS:

Using population health data from the Navarre region of Spain for the 2015/16 to 2019/20 influenza seasons, we conducted a test-negative case–control study to assess the effect of influenza vaccination in the current and 5 previous seasons. From patients presenting to hospitals and primary health care centres with influenza-like illness who underwent testing for influenza, we estimated the effects of influenza vaccination among patients with asthma overall and between those presenting as inpatients or outpatients, as well as between patients with and without asthma.

RESULTS:

Of 1032 patients who had asthma and were tested, we confirmed that 421 had influenza and the remaining 611 were test-negative controls. We found that the average effect of influenza vaccination was 43% (adjusted odds ratio [OR] 0.57, 95% confidence interval [CI] 0.40 to 0.80) for current-season vaccination regardless of previous doses, and 38% (adjusted OR 0.62, 95% CI 0.39 to 0.96) for vaccination in previous seasons only. Effects were similar for outpatients and inpatients. Among patients with asthma and confirmed influenza, current-season vaccination did not reduce the odds of hospital admission (adjusted OR 1.05, 95% CI 0.51 to 2.18). Influenza vaccination effects were similar for patients with and without asthma.

INTERPRETATION:

We estimated that, on average, current or previous influenza vaccination of people with asthma prevented almost half of influenza cases. These results support recommendations that people with asthma receive influenza vaccination.

Effect of Influenza Vaccination in Preventing Laboratory-Confirmed Influenza Hospitalization in Patients With Diabetes Mellitus

BACKGROUND

People with diabetes are at high risk of severe influenza complications. The influenza vaccination effect among diabetic patients remains inconclusive. We estimated the average effect of influenza vaccination status in the current and prior seasons in preventing laboratory-confirmed influenza hospitalization in diabetic patients.

METHODS

Patients attended in hospitals and primary healthcare centers with influenza-like illness were tested for influenza from the 2013-2014 to 2018-2019 seasons in Navarre, Spain. A test-negative case-control design in diabetic inpatients compared the influenza vaccination status in the current and 5 prior seasons between laboratory-confirmed influenza cases and negative controls. Vaccination status of influenza-confirmed cases was compared between diabetic inpatients and outpatients. Influenza vaccination effect was compared between diabetic patients and older (≥ 60 years) or chronic nondiabetic patients.

RESULTS

Of 1670 diabetic inpatients tested, 569 (34%) were confirmed for influenza and 1101 were test-negative controls. The average effect in preventing influenza hospitalization was 46% (95% confidence interval [CI], 28%-59%) for current-season vaccination and 44% (95% CI, 20%-61%) for vaccination in prior seasons only in comparison to unvaccinated patients in the current and prior seasons. Among diabetic patients with confirmed influenza, current-season vaccination reduced the probability of hospitalization (adjusted odds ratio, 0.35; 95% CI, .15-.79). In diabetic patients, vaccination effect against influenza hospitalizations was not inferior to that in older or chronic nondiabetic patients.

CONCLUSIONS

On average, influenza vaccination of diabetic population reduced by around half the risk of influenza hospitalization. Vaccination in prior seasons maintained a notable protective effect. These results reinforce the recommendation of influenza vaccination for diabetic patients.

Effectiveness of palivizumab in preventing respiratory syncytial virus infection in high-risk children

To date, there is no consensus regarding palivizumab prophylaxis for respiratory syncytial virus infection. The purpose of this study is to assess the effectiveness of palivizumab prophylaxis to prevent respiratory syncytial virus-related infection consultations and hospitalizations in high-risk children <2 y. We studied children <2 y of age with risk factors who had indication of palivizumab prophylaxis over eight epidemic seasons (2011–2012 to 2018–2019) in Navarra, Spain. Children positives for respiratory syncytial virus by reverse-transcription polymerase chain reaction were compared to negative testers. Palivizumab was indicated in 1,214 children <2 y of age with risk factors during 2011–2012 to 2018–2019 seasons. A total of 142 high-risk children tested for respiratory syncytial virus were included in the study. From the 35 respiratory syncytial virus-positive confirmed cases, 20 (57%) had received palivizumab versus 82 (77%) from the 107 negative controls. The effectiveness of prophylactic palivizumab was 70% (95% CI, 19%-90%) in preventing confirmed clinical infection and 82% (95% CI, 29%-96%) in preventing hospitalized cases. Our results show that palivizumab is notably effective for preventing laboratory-confirmed cases of respiratory syncytial virus and hospitalization in high-risk children <2 y of age. For children who have received palivizumab, the risk of getting sick remains high; thus, other preventive measures are necessary.

Effectiveness of COVID-19 vaccines in preventing SARS-CoV-2 infection and hospitalisation, Navarre, Spain, January to April 2021

COVID-19 vaccine effectiveness was evaluated in close contacts of cases diagnosed during January–April 2021. Among 20,961 contacts, 7,240 SARS-CoV-2 infections were confirmed, with 5,467 being symptomatic and 559 leading to hospitalisations. Non-brand-specific one and two dose vaccine effectiveness were respectively, 35% (95% confidence interval (CI): 25 to 44) and 66% (95% CI: 57 to 74) against infections, 42% (95% CI: 31 to 52) and 82% (95% CI: 74 to 88) against symptomatic infection, and 72% (95% CI: 47 to 85) and 95% (95% CI: 62 to 99) against COVID-19 hospitalisation. The second dose significantly increased effectiveness. Findings support continuing complete vaccination.

Surveillance for Enteroviruses Associated with Hand, Foot, and Mouth Disease, and Other Mucocutaneous Symptoms in Spain, 2006-2020

Hand, foot, and mouth disease (HFMD) is a mild illness caused by enteroviruses (EV), although in some Asian countries, large outbreaks have been reported in the last 25 years, with a considerable incidence of neurological complications. This study describes epidemiological and clinical characteristics of EV infections involved in HFMD and other mucocutaneous symptoms from 2006 to 2020 in Spain. EV-positive samples from 368 patients were included. EV species A were identified in 85.1% of those typed EV. Coxsackievirus (CV) A6 was the prevalent serotype (60.9%), followed by EV-A71 (9.9%) and CVA16 (7.7%). Infections affected children (1-6 years old) mainly, and show seasonality with peaks in spring-summer and autumn. Clinical data indicated few cases of atypical HFMD as well as those with neurological complications (associated with the 2016 EV-A71 outbreak). Phylogenetic analysis of CVA6 VP1 sequences showed different sub-clusters circulating from 2010 to present. In conclusion, HFMD or exanthemas case reporting has increased in Spain in recent years, probably associated with an increase in circulation of CVA6, although they did not seem to show greater severity. However, EV surveillance in mucocutaneous manifestations should be improved to identify the emergence of new types or variants causing outbreaks and more severe pathologies.

Influenza Vaccination and Risk of SARS-CoV-2 Infection in a Cohort of Health Workers

Vaccines may induce positive non-specific immune responses to other pathogens. This study aims to evaluate if influenza vaccination in the 2019-2020 season had any effect on the risk of SARS-CoV-2 confirmed infection in a cohort of health workers. During the first SARS-CoV-2 epidemic wave in Spain, between March and May 2020, a cohort of 11,201 health workers was highly tested by RT-qPCR and/or rapid antibody test when the infection was suspected. Later in June, 8665 of them were tested for total antibodies in serum. A total of 890 (7.9%) health workers were laboratory-confirmed for SARS-CoV-2 infection by any type of test, while no case of influenza was detected. The adjusted odds ratio between 2019-2020 influenza vaccination and SARS-CoV-2 confirmed infection was the same (1.07; 95% CI, 0.92-1.24) in both comparisons of positive testers with all others (cohort design) and with negative testers (test-negative design). Among symptomatic patients tested by RT-qPCR, the comparison of positive cases and negative controls showed an adjusted odds ratio of 0.86 (95% CI, 0.68-1.08). These results suggest that influenza vaccination does not significantly modify the risk of SARS-CoV-2 infection. The development of specific vaccines against SARS-CoV-2 is urgent.

Molecular epidemiology of an enterovirus A71 outbreak associated with severe neurological disease, Spain, 2016

Introduction

Enterovirus A71 (EV-A71) is an emerging pathogen that causes a wide range of disorders including severe neurological manifestations. In the past 20 years, this virus has been associated with large outbreaks of hand, foot and mouth disease with neurological complications in the Asia-Pacific region, while in Europe mainly sporadic cases have been reported. In spring 2016, however, an EV-A71 outbreak associated with severe neurological cases was reported in Catalonia and spread further to other Spanish regions.

Aim

Our objective was to investigate the epidemiology and clinical characteristics of the outbreak.

Methods

We carried out a retrospective study which included 233 EV-A71-positive samples collected during 2016 from hospitalised patients. We analysed the clinical manifestations associated with EV-A71 infections and performed phylogenetic analyses of the 3’-VP1 and 3Dpol regions from all Spanish strains and a set of EV-A71 from other countries.

Results

Most EV-A71 infections were reported in children (mean age: 2.6 years) and the highest incidence was between May and July 2016 (83%). Most isolates (218/233) were classified as subgenogroup C1 and 217 of them were grouped in one cluster phylogenetically related to a new recombinant variant strain associated with severe neurological diseases in Germany and France in 2015 and 2016. Moreover, we found a clear association of EV-A71-C1 infection with severe neurological disorders, brainstem encephalitis being the most commonly reported.

Conclusion

An emerging recombinant variant of EV-A71-C1 was responsible for the large outbreak in 2016 in Spain that was associated with many severe neurological cases.

Remaining Effect of Influenza Vaccines Received in Prior Seasons

This study evaluates the remaining effect of influenza vaccines received in the 5 prior seasons. During 7 influenza seasons, 8933 patients were enrolled and 47% were confirmed for influenza. Compared with unvaccinated individuals in the current and 5 prior seasons, vaccination was protective when the last dose had been received in the current season (40% [95% confidence interval {CI}, 32%-47%]), and 1 (42% [95% CI, 27%-54%]), 2-3 (35% [95% CI, 16%-49%]), or 4-5 seasons (31% [95% CI, 4%-51%]) prior. This effect lasted for fewer seasons in the elderly and in patients with chronic conditions. On average, several recent prior doses were as protective as current-season vaccination.

Enterovirus D68-associated respiratory and neurological illness in Spain, 2014-2018

During 2014, enterovirus D68 (EV-D68) outbreaks were described globally, causing severe respiratory diseases in children and, in some cases, subsequent paralysis. In this study, the type characterization of enterovirus (EV) detected in respiratory illnesses and the epidemiology and clinical association of EV-D68 infections in Spain over a five-year period were described. A total of 546 EV-positive samples from hospitalized patients with respiratory infections were included. EV-D68 was the most frequently detected type (46.6%, 191/410 typed EV). Other EV from species A (25.1%), B (27.8%) and C (0.5%) were also identified. EV-D68 infections were more associated with bronchitis while EV-A/B types were more frequent in upper respiratory illness (p < 0.01). EV-D68 was also detected in patients with neurological symptoms (nine meningitis/meningoencephalitis and eight acute flaccid paralysis cases). Phylogenetic analysis of 3′-VP1 region showed most Spanish EV-D68 sequences from 2014 to 2016 belonged to subclades B2/B3, as other American and European strains circulating during the same period. However, those detected in 2017 and 2018 clustered to the emerged subclade D1. In summary, different EV can cause respiratory infections but EV-D68 was the most prevalent, with several strains circulating in Spain at least since 2014. Association between EV-D68 infection and neurological disease was also described.

Infections due to Cellulosimicrobium species: case report and literature review

Background

Cellulosimicrobium species, formely known as Oerskovia species, are gram-positive bacilli belonging to the order Actinomycetales. They rarely cause human infections. The genus comprises two pathogenic species in humans: C. cellulans and C. funkei. Based on a case report, we provide a review of the literature of infections caused by Cellulosimicrobium/Oerskovia, in order to improve our knowledge of this unusual infection.

Case presentation

An 82-year-old woman with aortic prosthetic valve presented to the hospital with fever and heart failure. Further work up revealed the diagnosis of C. cellulans infective endocarditis (IE). The strain was identified by MALDI-TOF MS, API Coryne and 16S rRNA sequencing. The patient was deemed not to be an operative candidate and died despite the antibiotic therapy 35 days after admission.

Conclusions

Reviewing cases of Cellulosimicrobium species infections and communicating the successful and unsuccessful clinical experiences can assist future healthcare providers. Our case and those previously reported indicate that Cellulosimicrobium species usually infect immunocompromised patients or foreign body carriers. The most frequent pattern of infection is central venous catheter related bacteremia. The optimal treatment should include foreign body removal and valve surgery should be considered in case of IE.

Interim effectiveness of trivalent influenza vaccine in a season dominated by lineage mismatched influenza B, northern Spain, 2017/18

The 2017/18 interim estimate of trivalent influenza vaccine effectiveness (VE) was 39% (95% confidence interval: 20-54) in Navarre. Compared with individuals unvaccinated in the current and five previous seasons, VE against influenza B was 41% for current and any prior doses, 67% for current vaccination only, and 22% for any prior doses, and 43%, 51% and 54%, respectively against influenza A(H3N2). This suggests moderate VE despite predominance of lineage mismatched influenza B.

Detection of Respiratory Viruses in Deceased Persons, Spain, 2017

During the 2016–17 influenza season in Spain, we tested specimens from 57 elderly deceased persons for respiratory viruses. Influenza viruses were detected in 18% of the specimens and any respiratory virus in 47%. Only 7% of participants had received a diagnosis of infection with the detected virus before death.

Comparison of influenza vaccine effectiveness in preventing outpatient and inpatient influenza cases in older adults, northern Spain, 2010/11 to 2015/16

We compared trivalent inactivated influenza vaccine effectiveness (VE) in preventing outpatient and inpatient influenza cases in Navarre, Spain. Methods: During seasons 2010/11 to 2015/16, community-dwelling patients with influenza-like illness aged 50 years or older were tested for influenza when attended by sentinel general practitioners or admitted to hospitals. The test–negative design was used to estimate and compare the VE by healthcare setting. Results: We compared 1,242 laboratory-confirmed influenza cases (557 outpatient and 685 inpatient cases) and 1,641 test-negative controls. Influenza VE was 34% (95% confidence interval (CI): 6 to 54) in outpatients and 32% (95% CI: 15 to 45) in inpatients. VE in outpatients and inpatients was, respectively, 41% (95% CI: –1 to 65) and 36% (95% CI: 12 to 53) against A(H1N1)pdm09, 5% (95% CI: –58 to 43) and 22% (95% CI: –9 to 44) against A(H3N2), and 49% (95% CI, 6 to 73) and 37% (95% CI: 2 to 59) against influenza B. Trivalent inactivated influenza vaccine was not associated with a different probability of hospitalisation among influenza cases, apart from a 54% (95% CI: 10 to 76) reduction in hospitalisation of influenza A(H3N2) cases. Conclusions: On average, influenza VE was moderate and similar in preventing outpatient and inpatient influenza cases over six influenza seasons in patients above 50 years of age. In some instances of low VE, vaccination may still reduce the risk of hospitalisation in older adults with vaccine failure.

[Uncomplicated urinary tract infections. Antimicrobial susceptibility study in Navarre]

BACKGROUND

Urinary tract infection (UTI) is a high prevalence infection at the community level. In order to improve the adequacy of the empirical therapy, we evaluated the etiology and the resistance pattern of the main uropathogens responsible for community acquired UTI in Navarre.

METHODS

Retrospective study (2014-2016) in which we included microorganisms recovered with significant counts from samples of patients with community-acquired UTI. The global etiology and etiology according to age and sex was analyzed. Antimicrobial resistance was studied with urotopathogens isolated in 2016.

RESULTS

Escherichia coli was the most frequently isolated microorganism both in the population (60.8%) and in each of the groups analyzed according to age and sex. The sensitivity of E. coli was: nitrofurantoin 97.4%, fosfomycin 96.5% amoxicillin-clavulanic acid 83.8%, trimethoprim-sulfamethoxazole 68.3%, quinolones 63.4% and amoxicillin 41.9%. Pooled sensitivity shows that the sensitivity to fosfomycin was 83.4% in men <15 years, 89.4% in women <15 years and 81.9% in women between 15-65 years; and to nitrofurantoin was 86.7% in women <15 years and 82.2% in women between 15-65 years.

CONCLUSIONS

E. coli continues to be the most frequent microorganism in community-acquired UTI with a rate of sensitivity to fosfomycin and nitrofurantoin above 95%. The empirical treatment of UTI in our environment should not include amoxicillin, amoxicillin-clavulanic acid, trimethoprim-sulfamethoxazole or quinolones. Fosfomycin may be empirically used in the treatment of uncomplicated cystitis in men younger than 15 years and in women under 65 years, and nitrofurantoin may be used empirically in women under 65 years.

Effect of Repeated Vaccination With the Same Vaccine Component Against 2009 Pandemic Influenza A(H1N1) Virus

Background

The 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) vaccine component has remained unchanged from 2009. We estimate the effectiveness of current and prior inactivated influenza A(H1N1)pdm09 vaccination from influenza seasons 2010-2011 to 2015-2016.

Methods

Patients attended with influenza-like illness were tested for influenza. Four periods with continued A(H1N1)pdm09 circulation were included in a test-negative design.

Results

We enrolled 1278 cases and 2343 controls. As compared to individuals never vaccinated against influenza A(H1N1)pdm09, the highest effectiveness (66%; 95% confidence interval, 49%-78%) was observed in those vaccinated in the current season who had received 1-2 prior doses. The effectiveness was not statistically lower in individuals vaccinated in the current season only (52%) or in those without current vaccination and >2 prior doses (47%). However, the protection was lower in individuals vaccinated in the current season after >2 prior doses (38%; P = .009) or those currently unvaccinated with 1-2 prior doses (10%; P < .001). Current-season vaccination improved the effect in individuals with 1-2 prior doses and did not modify significantly the risk of influenza in individuals with >2 prior doses.

Conclusion

Current vaccination or several prior doses were needed for high protection. Despite the decreasing effect of repeated vaccination, current-season vaccination was not inferior to no current-season vaccination.

Combined effectiveness of prior and current season influenza vaccination in northern Spain: 2016/17 mid-season analysis

The 2016/17 mid-season vaccine effectiveness estimate against influenza A(H3N2) was 15% (95% confidence interval: −11 to 35) in Navarre. Comparing to individuals unvaccinated in the current and four prior seasons, effectiveness was 24% for current and 3–4 prior doses, 61% for current and 1–2 prior doses, 42% for only current vaccination, and 58% for 3–4 prior doses. This suggests moderate effectiveness for different combinations of vaccination in the current and prior seasons.

Effects of previous episodes of influenza and vaccination in preventing laboratory-confirmed influenza in Navarre, Spain, 2013/14 season

We estimated whether previous episodes of influenza and trivalent influenza vaccination prevented laboratory-confirmed influenza in Navarre, Spain, in season 2013/14. Patients with medically-attended influenza-like illness (MA-ILI) in hospitals (n = 645) and primary healthcare (n = 525) were included. We compared 589 influenza cases and 581 negative controls. MA-ILI related to a specific virus subtype in the previous five seasons was defined as a laboratory-confirmed influenza infection with the same virus subtype or MA-ILI during weeks when more than 25% of swabs were positive for this subtype. Persons with previous MA-ILI had 30% (95% confidence interval (CI): -7 to 54) lower risk of MA-ILI, and those with previous MA-ILI related to A(H1N1)pdm09 or A(H3N2) virus, had a, respectively, 63% (95% CI: 16-84) and 65% (95% CI: 13-86) lower risk of new laboratory-confirmed influenza by the same subtype. Overall adjusted vaccine effectiveness in preventing laboratory-confirmed influenza was 31% (95% CI: 5-50): 45% (95% CI: 12-65) for A(H1N1)pdm09 and 20% (95% CI: -16 to 44) for A(H3N2). While a previous influenza episode induced high protection only against the same virus subtype, influenza vaccination provided low to moderate protection against all circulating subtypes. Influenza vaccine remains the main preventive option for high-risk populations.

[Comparative study of HIV-1/2 antibody confirmatory assay: Geenius™ versus INNO-LIA™]

OBJECTIVE

The aim of the study is to compare two confirmatory tests for HIV-1/2 infection.

METHODS

A prospective study was carried out between 01/01/2015 and 12/31/2015. Serum samples with repeatedly positive results in the Antibody-Antigen-HIV-1/2 (Architect, Abbott) screening assay were included. The serum samples corresponding to new diagnosed cases were selected and were used to compare the two confirmatory assays: Geenius™ HIV-1/2 (Bio-Rad) and INNO-LIA™ HIV-1/2 score line-immunoassay (Innogene-tics®). The HIV-1 viral load (Cobas® AmpliPrepHIV, Ro-che) was performed in discordant or indeterminate cases.

RESULTS

Eight five samples were included. The results of both confirmatory assays were concordant in 80/85 samples: 53 HIV-1, 1 HIV-2, 25 negative and one indeterminate. Cohen's Kappa concordance coefficient between Geenius™ and INNO-LIA™ techniques was very high (0.878).

CONCLUSIONS

The concordance between the two assays is high. The procedure for Geenius™ is simple and fast. Geenius™ is a good alternative to include in the HIV-1/2 diagnostic algorithm.

Source identification of autochthonous-introduced Plasmodium vivax Malaria, Spain

In 2014, an autochthonous case of introduced malaria caused by Plasmodium vivax was identified in Spain. The strain that infected this patient was identical to that of a prior imported case from Pakistan. This is the first case where the source of infection could be identified since elimination in Spain.

Influenza vaccine effectiveness in preventing inpatient and outpatient cases in a season dominated by vaccine-matched influenza B virus

Studies that have evaluated the influenza vaccine effectiveness (VE) to prevent laboratory-confirmed influenza B cases are uncommon, and few have analyzed the effect in preventing hospitalized cases. We have evaluated the influenza VE in preventing outpatient and hospitalized cases with laboratory-confirmed influenza in the 2012-2013 season, which was dominated by a vaccine-matched influenza B virus. In the population covered by the Navarra Health Service, all hospitalized patients with influenza-like illness (ILI) and all ILI patients attended by a sentinel network of general practitioners were swabbed for influenza testing, and all were included in a test-negative case-control analysis. VE was calculated as (1-odds ratio) × 100. Among 744 patients tested, 382 (51%) were positive for influenza virus: 70% for influenza B, 24% for A(H1N1)pdm09, and 5% for A(H3N2). The overall estimate of VE in preventing laboratory-confirmed influenza was 63% (95% confidence interval (CI): 34 to 79), 55% (1 to 80) in outpatients and 74% (33 to 90) in hospitalized patients. The VE was 70% (41 to 85) against influenza B and 43% (-45 to 78) against influenza A. The VE against virus B was 87% (52 to 96) in hospitalized patients and 56% in outpatients (-5 to 81). Adjusted comparison of vaccination status between inpatient and outpatient cases with influenza B did not show statistically significant differences (odds ratio: 1.13; p = 0.878). These results suggest a high protective effect of the vaccine in the 2012-2013 season, with no differences found for the effect between outpatient and hospitalized cases.

Effectiveness of subunit influenza vaccination in the 2014-2015 season and residual effect of split vaccination in previous seasons

BACKGROUND

In Navarra, Spain, subunit vaccine was first used in the 2014-2015 season, whereas trivalent split-virion influenza vaccines had been used in previous seasons. We estimate the effectiveness of the subunit vaccine in the current season and split vaccine in the two previous seasons against laboratory-confirmed influenza in the 2014-2015 season.

METHODS

Patients with influenza-like illness hospitalized or attended by sentinel general practitioners were swabbed for influenza testing. The previous and current vaccine status of laboratory-confirmed cases was compared to test-negative controls.

RESULTS

Among 1213 patients tested, 619 (51%) were confirmed for influenza virus: 52% influenza A(H3N2), 46% influenza B, and 2% A(H1N1)pdm09. The overall effectiveness for subunit vaccination in the current season was 19% (95% confidence interval [CI]: -13 to 42), 2% (95%CI: -47 to 35) against influenza A(H3N2) and 32% (95%CI: -4 to 56) against influenza B. The effectiveness against any influenza was 67% (95%CI: 17-87) for 2012-2013 and 2013-2014 vaccination only, 42% (95%CI: -31 to 74) for 2014-2015 vaccination only, and 38% (95%CI: 8-58) for vaccination in the 2012-2013, 2013-2014 and 2014-2015 seasons. The same estimates against influenza A(H3N2) were 47% (95%CI: -60 to 82), -54% (95%CI: -274 to 37) and 28% (95%CI: -17 to 56), and against influenza B were 82% (95%CI: 19-96), 93% (95%CI: 45-99) and 43% (95%CI: 5-66), respectively.

CONCLUSION

These results suggest a considerable residual protection of split vaccination in previous seasons, low overall effectiveness of current season subunit vaccination, and possible interference between current subunit and previous split vaccines.

Reduced incidence of invasive pneumococcal disease after introduction of the 13-valent conjugate vaccine in Navarre, Spain, 2001-2013

Pneumococcal conjugate vaccines (PCVs) were licensed for use in children and became available for private purchase in Spain in 2001 (PCV7), 2009 (PCV10) and 2010 (PCV13). This study evaluates changes in the incidence of invasive pneumococcal disease (IPD) and the pattern of serotypes isolated in Navarre, Spain, between the period of use of PCV7 (2004-2009) and that of PCV13 (2010-2013). The percentage of children <2 years who received at least one dose of PCV in these periods ranged from 25 to 61% and 61 to 78%, respectively. Between the periods 2004-2009 and 2010-2013 IPD incidence declined by 37%, from 14.9 to 9.4 cases/100,000 inhabitants (p<0.001). In children <5 years it fell by 69% (p<0.001), in persons aged 5-64 years, by 34% (p<0.001), and in those ≥ 65, by 23% (p=0.024). The incidence of cases due to PCV13 serotypes declined by 81% (p<0.001) in children <5 years and by 52% (p<0.001) in the whole population. No significant changes were seen in the distribution of clinical presentations or in disease severity. The incidence of IPD has declined and the pattern of serotypes causing IPD has changed notably in children and moderately in adults following the replacement of PCV7 by PCV13.

Vaccine effectiveness in preventing laboratory-confirmed influenza in Navarre, Spain: 2013/14 mid-season analysis

We estimate mid-2013/14 season vaccine effectiveness (VE) of the influenza trivalent vaccine in Navarre, Spain. Influenza-like illness cases attended in hospital (n=431) and primary healthcare (n=344) were included. The overall adjusted VE in preventing laboratory-confirmed influenza was 24% (95% CI: -14 to 50). The VE was 40% (95% CI: -12 to 68) against influenza A(H1)pdm09 and 13% (95% CI: -36 to 45) against influenza A(H3). These results suggest a moderate preventive effect against influenza A(H1)pdm09 and low protection against influenza A(H3).

[Imported histoplasmosis in Navarra: presentation of four cases]

OBJECTIVE

Histoplasmosis is a fungal infection caused by the dimorphic fungi Histoplasma capsulatum. Its incidence in Spain has increased in recent years, mainly due to the increased presence of immigrants from Latin America and increased travel to the continent for tourism and cooperation. Our aim was to review the clinical characteristics of cases of histoplasmosis diagnosed in our hospital during the last six years.

CASE REPORTS

We diagnosed 4 cases from 4 patients from South America, 3 of whom were HIV positive and 1 diagnosed with dermatomyositis was treated with immunosuppressive drugs. The laboratory diagnosis was carried out by histological and microbiological study, by culture and specific PCR directly on the sample.

DISCUSSION

As it is an imported infection there needs to be a high level of suspicion and a detailed history taken to get a diagnosis. This infection requires a differential diagnosis between febrile syndrome in immunosuppressed patients, both HIV positive and immunosuppressive therapy, which originate from endemic areas, or who have a history of staying in them.

[Loa Loa and Mansonella perstans coinfection in a patient from Guinea]

We present a case of mixed infection by two filariae (Loa loa and Mansonella perstans). It seems that the infection was suspected due to a pronounced eosinophilia in a routine analysis. Sheathed and unsheathed microfilariae were observed in the spread of peripheral blood, which enabled a diagnosis to be established of mixed infection by filariae. The definitive diagnosis of the species was carried out at the National Centre of Microbiolgy of Majadahonda. A treatment was initiated with dietilcarbamazina and mebendazole which resulted in the patient's being cured and in the elimination of the microfilariae in the patient's blood. Filariasis is still endemic in many countries. Due to the increase of travellers to such zones and the migratory movements from such areas it is not unusual for us to come across such a diagnosis. The implantation of massive treatments against filariae in endemic zones by the World Health Organisation is reducing their transmission and is managing to eliminate the disease in some areas.

[Clinical relevance of nontuberculous mycobacteria]

BACKGROUND

The isolation of nontuberculous mycobacteria (NTM) has increased in recent years largely due to the use of liquid cultivation media. In many cases such isolations lack clinical relevance, which is why the evaluation of their meaning must be carried out on the basis of international clinical criteria. This article studies the impact of using the criteria that the American Thoracic Society (ATS) has established for differentiating an infection of NTM colonisation in respiratory samples.

METHODS

Microbiological and clinical study of the patients with repeated isolations of NTM in respiratory samples registered in our laboratory between 2000 and 2004.

RESULTS

One hundred and sixteen positive cultivations of NTM were obtained, repeatedly isolated in 46 episodes corresponding to 42 patients. Eleven different species were identified: M. xenopi (16 cases), M. avium (12), M. kansasii (7), M. fortuitum (5), M. malmoense (2) and, finally, 1 of each of the following: M. genavense, M. simiae, M. gordonae and M. lentiflavum. It was possible to study 36 patients, of whom 17 met the criteria of the ATS, and, out of these, only 12 received specific treatment. In those cases that did not meet the ATS criteria the isolations did not have any clinical repercussion. In both the treated and untreated groups a clearly differentiated evolution was not observed.

CONCLUSIONS

Facing the difficulty of attributing an etiological role to an NTM of respiratory samples, it is necessary to follow international criteria such as those of the ATS before beginning a specific treatment in order to avoid the incorrect treatment of patients.

Valoración de la prueba de amplificación MTD-2 para la detección directa de Mycobacterium tuberculosis en la muestra

BACKGROUND

To evaluate the utility of the Amplified Mycobacterium Tuberculosis Direct Test (MTD-2, Gen-Probe) in the microbiological diagnosis of tuberculosis.

METHODS

We evaluated the results obtained in 146 specimens with the MTD-2 test, together with those of the culture and smears. The MTD-2 test was performed on all the smear positives specimens (n=47), on the smear-negative specimens, when the test was demanded (n=19), and in other smear-negative specimens previously selected, according to the clinical history of the patient (n=80). We considered real cases of tuberculosis, those that were culture positive for Mycobacterium tuberculosis and those that were specifically treated.

RESULTS

The overall sensitivity, specificity, positive and negative predictive values for the MTD test were: 95, 76, 71, and 96%, for the culture; and 84, 100, 100 and 90% and 75, 94, 89 and 86% for the smears, respectively. In smear positive specimens, the test showed a great specificity, and differentiated M. tuberculosis from other mycobacteria. In the smear negatives, the sensitivity of the test was low and so was the positive predictive value, especially in series performed with a high work load.

CONCLUSIONS

Data from our study show that the MTD-2 test is a reliable method for rapid diagnosis of tuberculosis in smear positive specimens. However, due to its low sensitivity and positive predictive value, it is not recommended in the routine diagnosis of tuberculosis. Also, for this reason, whenever a positive result is obtained with a smear negative specimen, the result needs to be confirmed with another specimen.

Estudio de la resistencia de Mycobacterium tuberculosis a los principales tuberculostáticos (Hospital de Navarra 1996-2003)

INTRODUCTION

The aim of this study was to evaluate the sensitivity to the principal tuberculostatics of the M. tuberculosis stocks isolated in our laboratory and to study the factors related to resistance.

METHODS

Study of 475 stocks of M. tuberculosis corresponding to all cases diagnosed in the eight year period between 1996 and 2003. We employed the BACTEC 460TB system, together with Lowenstein solid medium, in the cultivation of the samples. The sensitivity studies were carried out using the BACTEC 460TB system.

RESULTS AND CONCLUSIONS

Both the incidence and the number of cases of resistant tuberculosis showed oscillations over the eight years of the study. The fact that there is no homogeneous tendency makes it necessary to maintain active surveillance of this process. Global resistance to isoniacide was 8%, making it is convenient to carry out sensitivity studies in all the diagnosed cases. The cases of multiresistant tuberculosis (resistant to at least isoniacide and rifampicin), did not exceed 3%. The prognosis of the patients with resistant tuberculosis was bleak in cases of coinfection with HIV; however, when the immunological defences were conserved, and guidelines for treatment with active drugs were provided, the recovery of the majority of the patients was achieved. At present, sensitive and rapid procedures are available to us, making it recommendable to study the sensitivity of all the stocks of M. tuberculosis that are isolated; this is essential in the case of HIV positive or immigrant patients.