The Pertussis resurgence: putting together the pieces of the puzzle

Pertussis vaccine effectiveness following country-wide implementation of a hexavalent acellular pertussis immunization schedule in infants and children in Panama

Despite high pediatric vaccination coverage rates (VCRs), pertussis incidence has increased worldwide, including in several countries in Latin America in the last two decades. Given the few vaccine effectiveness (VE) studies in Latin American countries, this retrospective, observational, cohort study estimated the effectiveness of hexavalent acellular (aP) primary and booster vaccination (wP) against pertussis in infants (6.5-18.5 months) and children (18.5-48.5 and 48.5-72.5 months) in Panama. Age-specific incidence rates (IRs) were calculated for the vaccine's pre-initiation (2001-2013), initiation (2014), and post-initiation (2015-2019) periods. VCRs and trends were determined, and VE was analyzed using a case coverage or screening method to compare proportions of vaccinated cases and vaccinated individuals in the population. Between 2001-2019, 868 confirmed pertussis cases were reported in Panama; 712 (82.0%; 54.8 cases/year) during the pre-initiation period, 19 (2.2%; 19 cases/year) during the initiation period, and 137 (15.8%; 27.4 cases/year) during the post-initiation period. Panama underwent cyclical increases in IRs, which varied between age groups. VCRs increased for primary and booster doses. Between 2015 and 2019, third-dose yearly vaccine coverage increased, on average, 3.3%. Specifically, during the post-initiation period, 109/137 (79.6%) of cases were unvaccinated. Relative VE was estimated at 96.2% [95% CI: 86.5%, 98.9%] with three doses; 100% with 4 and 5 booster doses. Absolute VE was estimated at 99.3% with three doses only. These results show that vaccination played an important role in maintaining a low number of pertussis cases in Panama, affirming the need for sustained investment and commitment to vaccination programs.

The Present and Future Aspects of Life-Long Pertussis Prevention: Narrative Review with Regional Perspectives for Türkiye

Pertussis, caused by Bordetella pertussis, remains one of the most widespread, contagious, and vaccine-preventable diseases. It results in notable morbidity and mortality as well as severe medical, social, and economic burden. Despite high global vaccine coverage, pertussis continues to be a significant epidemiologic problem, with outbreak episodes every few years just as in the pre-vaccination era. In Türkiye, there is a lack of comprehensive data on the current burden of pertussis in different age and risk groups, leading to underdiagnosis and underreporting of the disease, especially in adults who are often not considered at risk. Available data from Türkiye also reveal inadequate levels of protective antibodies in preterm newborns, emphasizing the need for additional preventive measures. Authors stated that improving physician awareness of pertussis symptoms in patients with prolonged cough, increasing access to routine pertussis tests, and conducting surveillance studies would aid in accurate diagnosis and reporting in Türkiye. As the Turkish Ministry of Health Antenatal Care Management Guide suggests routine second and third pregnancy check-up visits at weeks 18-24 and 28-32 correspondingly, this period can be considered the ideal vaccination time for Türkiye. Introducing a booster dose of Tdap at around 10 years of age or during national military service would reduce transmission and protect susceptible individuals. Identifying individuals at high risk of severe pertussis and prioritizing them for a booster dose is also crucial in Türkiye. Enhancing surveillance systems, increasing healthcare professionals' awareness through training, and organizing catch-up visits for missed vaccinations during the COVID-19 pandemic are mentioned as additional strategies to improve pertussis prevention in Türkiye. This review focuses on the global and regional burden of pertussis and obstacles to effective prevention and evaluates existing strategies to achieve lifelong pertussis prevention. Literature and current strategies were also discussed from a Turkish national standpoint.

Impact of maternal whole-cell or acellular pertussis primary immunization on neonatal immune response

With the introduction of pertussis immunization for pregnant women in many countries, there has been renewed interest in the impact of whole-cell pertussis vaccine (wP) versus acellular vaccine (aP) on disease control, particularly regarding the best approach for priming. To gather evidence on this topic, we analyzed the impact of aP or wP priming on aP vaccination during pregnancy (aPpreg) in mice. Two-mother vaccination schemes were employed (wP-wP-aPpreg and aP-aP-aPpreg), and the immune response in the mothers and their offspring, as well as the protection of the offspring against Bordetella pertussis challenge, were assessed. Pertussis toxin (PTx)-specific IgG responses were detected in mothers after both the second and third doses, with higher titers after the third dose, regardless of the vaccination schedule. However, a significant reduction in PTx-IgG levels was observed after 22 weeks post aPpreg immunization in mothers with the aP-aP-aPpreg scheme but not in the wP-wP-aPpreg immunized mothers. The aP-aP-aPpreg schedule triggered a murine antibody response mainly to a Th2-profile, while wP-wP-aPpreg induced a Th1/Th2 mixed profile. Both immunization schemes administered to the mothers protected the offspring against pertussis, but the wP-wP-aPpreg vaccination conferred offspring protection in all pregnancies at least up to 20 weeks after receiving the aPpreg-dose. In contrast, the immunity induced by aP-aP-aPpreg began to decline in births that occurred 18 weeks after receiving the aPpreg dose. For the aP-aP-aPpreg scheme, pups born from gestations furthest from aPpreg (+22 weeks) had lower PTx-specific IgG levels than those born closer to the application of the dose during pregnancy. In contrast, for pups born to wP-wP-aPpreg vaccinated mothers, the PTx-specific IgG levels were maintained over time, even for those born at the longest time studied (+22 weeks). It is noteworthy that only the pups born from mothers with aP-aP-aPpreg and receiving a neonatal dose of either aP or wP were more susceptible to B. pertussis infection than mice with only maternal immunity, suggesting interference with the induced immunity (p<0.05). However, it should be noted that mice with maternal immunity, whether vaccinated or not with neonatal doses, are better protected against colonization with B. pertussis than mice without maternal immunity but vaccinated with aP or wP.

Novel approaches to reactivate pertussis immunity

INTRODUCTION

Whole cell and acellular pertussis vaccines have been very effective in decreasing the deaths of neonates and infants from Bordetella pertussis. Despite high vaccine coverage worldwide, pertussis remains one of the most common vaccine-preventable diseases, thus suggesting that new pertussis vaccination strategies are needed. Several candidates are currently under development, such as acellular pertussis vaccines that use genetically detoxified pertussis toxin, acellular pertussis vaccines delivered with new adjuvants or new delivery systems, or an intranasally delivered, live attenuated vaccine.

AREAS COVERED

This review discusses the different possibilities for improving current pertussis vaccines and the present state of knowledge on the pertussis vaccine candidates under development.

EXPERT OPINION

Until there is a safe, effective, and affordable alternative to the two types of existing vaccines, we should maintain sufficient childhood coverage and increase the vaccination of pregnant women, adolescents, and young adults.

Characterization of prostanoids response to Bordetella pertussis antigen BscF and Tdap in LPS-challenged monocytes

Prostanoids are potent inflammatory mediators that play a regulatory role in the innate immune activation of the adaptive immune response to determine the duration of protection against infection. We aim to quantify the modulation of prostanoids profiles in lipopolysaccharide (LPS)-stimulated THP-1 cells treated with the novel pertussis antigen BscF. We compared the effect with pertussis antigens present in the current Tdap vaccine to understand the immunomodulatory effect that might contribute to the diminished Tdap vaccine effectiveness. The inflammatory challenge with LPS induced a robust elevation of most prostanoid family members compared to the control treatment. Treatment with BscF and Tdap significantly reduced the LPS-stimulated elevation of prostaglandins (PGs) D2, E2, and F2α, as well as thromboxane (TX) A2 levels. An opposite trend was observed for PGI2, as both antigens accelerated the LPS-stimulated upregulation. Further, we quantified cyclooxygenases (COXs) that catalyze the biosynthesis of prostanoids and found that both antigens significantly reduced LPS-stimulated COX-1 and COX-2, demonstrating that the waning of acellular pertussis vaccines' protective immunity may be due to other downstream enzymes not related to COXs. Our present study validates the potential role of BscF as an adjuvant, resulting in the next-generation pertussis vaccine discovery.

Precision Vaccine Development: Cues From Natural Immunity

Traditional vaccine development against infectious diseases has been guided by the overarching aim to generate efficacious vaccines normally indicated by an antibody and/or cellular response that correlates with protection. However, this approach has been shown to be only a partially effective measure, since vaccine- and pathogen-specific immunity may not perfectly overlap. Thus, some vaccine development strategies, normally focused on targeted generation of both antigen specific antibody and T cell responses, resulting in a long-lived heterogenous and stable pool of memory lymphocytes, may benefit from better mimicking the immune response of a natural infection. However, challenges to achieving this goal remain unattended, due to gaps in our understanding of human immunity and full elucidation of infectious pathogenesis. In this review, we describe recent advances in the development of effective vaccines, focusing on how understanding the differences in the immunizing and non-immunizing immune responses to natural infections and corresponding shifts in immune ontogeny are crucial to inform the next generation of infectious disease vaccines.

Evaluating the impact of a continued maternal pertussis immunisation programme in England: A modelling study and cost-effectiveness analysis

INTRODUCTION

An unexpected resurgence of pertussis cases and infant deaths was observed in some countries that had switched to acellular pertussis vaccines in the primary immunisation schedule. In response to the outbreaks, maternal pertussis vaccination programmes in pregnant women have been adopted worldwide, including the USA in 2011 and the UK in 2012. Following the success of the programme in England, we evaluated the health and economic impact of stopping versus continuing the maternal pertussis immunisation to inform public health policy making.

METHODS

We used a mathematical model to estimate the number of infant hospitalisations and deaths related to pertussis in England over 2019-2038. Losses in quality-adjusted life years, QALYs, were considered for infants (aged 0-2 months) who survived or died from pertussis, bereaved parents (of infants who died from pertussis), and women with pertussis (aged 20-44 years). Direct medical costs to the National Health Service included infant hospitalisations, maternal vaccinations, and disease in women. Costs and QALYs were discounted at 3.5%. Changes in the incremental cost-effectiveness ratio, ICER, were explored in sensitivity analyses.

RESULTS

The model supports continuing the maternal pertussis immunisation programme as a cost-effective intervention at an ICER of £14,500/QALY (2.5% and 97.5%-quantile: £7,300/QALY to £32,400/QALY). Stopping versus continuing the maternal programme results in an estimated mean of 972 (range 582 to 1489) versus 308 (184 to 471) infant hospitalisations annually. Results were most sensitive to the number of hospitalisations and deaths when stopping the maternal programme. At a cost-effectiveness threshold of £30,000/QALY, the probability of the maternal programme being cost-effective was 96.2%.

CONCLUSION

Our findings support continuing the maternal pertussis vaccination programme as otherwise higher levels of disease activity and infant mortality are expected to return. These results have led policy makers to decide to continue the maternal programme in the UK routine immunisation schedule.

Clinical repercussions in pertussis infants post-Tdpa vaccination of pregnant woman: An immunization success?

INTRODUCTION

In 2014, there was an epidemic of pertussis in Brazil that caused the death of 129 infants. To control the disease amongst infants under 6 months of age, and especially those under 2 months, the Brazilian Ministry of Health introduced Tdap immunization for all pregnant women.

METHODS

This study aimed to describe the morbidity and mortality variables of pertussis cases in 969 infants aged under 6 months, comparing the periods before and after the introduction of Tdap vaccine in pregnant women. Data was extracted from the Information System on Notifiable Diseases (SINAN) including every case of pertussis that occurred in the metropolitan region of Recife-Brazil in infants under 6 months from January 2009 to October 2018. In order to analyze the variables, patients were divided into two groups Pre-Tdap(2009-2014), and Post-Tdap (2016-2018).

RESULTS

There were no significant differences between the age groups and gender distribution in the period compared. In the Post- Tdap group compared with the Pre-Tdap group, the clinical presentation of pertussis in infants differed with more paroxysmal cough, and more vomiting, less apnea, and cyanosis. During this period, there were fewer complications and no deaths occurred.

CONCLUSIONS

Maternal immunization with Tdap decreased disease severity, complication rates, and no deaths occurred in infants under 6 months of age diagnosed with pertussis.

Angioedema as a predominant symptom of Bordetella pertussis infection

A 41-year-old woman was referred to our hospital with a 6-week history of severe angioedema, dyspnoea and coughing. Initial investigations focused on common causes of angioedema. Clinical presentation and resistance to treatment with antihistamines and steroids made histamine-mediated angioedema unlikely. Bradykinin-mediated angioedema, such as hereditary or drug-induced angioedema, was excluded by a thorough history investigation and laboratory testing for C1-esterase and C4.

In rare cases, exogen pathogens cause angioedema. After profound testing for respiratory pathogens, Bordetella pertussis toxins IgA and IgG were found to be positive, indicating recent B. pertussis infection. Pertussis toxin may be responsible for increased vascular permeability causing angioedema. With adequate antibiotic treatment, the symptoms resolved quickly.

This case is an example of an atypical presentation of B. pertussis infection in an unvaccinated adult. The recent resurgence of pertussis makes early diagnosis and disease prevention by vaccination crucial.

Cost-effectiveness analysis of universal adult immunization with tetanus-diphtheria-acellular pertussis vaccine (Tdap) versus current practice in Brazil

BACKGROUND

A pertussis outbreak occurred in Brazil from 2011 to 2014, despite high coverage of whole-cell pertussis containing vaccines in early childhood. Infants were the most affected. This study aimed to evaluate the cost-effectiveness of introducing universal adult vaccination with Tdap into the National Immunization Program in Brazil.

METHODS

Economic evaluation using a dynamic model to compare two strategies: (1) universal vaccination with single dose of Tdap at 20 years of age and (2) current practice (only pregnant women pertussis vaccination). The health system perspective was adopted. Temporal horizon was 10 years. Discount rate of 5% was applied to costs and benefits. Vaccine effectiveness (VE) was obtained from a population-based observational study. Epidemiological, resource utilization and cost estimates were obtained from the Brazilian Health Information Systems. The primary outcome was cost per life year saved (LYS), based on life expectancy at birth in Brazil in 2015. Univariate and multivariate sensitivity analysis were performed.

RESULTS

Adult vaccination with VE of 82.6% and coverage of 40%, at price of US$7.01 per dose, and assuming herd protection would avoid 167 infant deaths by pertussis, saving 12,325 years of life and costing a total of US$105495891.61, from the health system perspective. The universal immunization would result in ICER of US$8459.13. The results were highly sensitive to disease incidence.

CONCLUSIONS

The results suggest that universal adult vaccination with Tdap would not be a cost-effective intervention for preventing pertussis cases and deaths in infants in Brazil.

Papel del estado de portador en el control de enfermedades infecciosas y su relación con la vacunación

El reservorio natural de Streptococcus pneumoniae, Neisseria meningitidis y Bordetella pertussis es el ser humano. De este modo, en caso de disponer de vacunas efectivas que impidieran la colonización por estas bacterias se podría interrumpir su transmisión. La respuesta inmune frente a los antígenos capsulares de Streptococcus pneumoniae condiciona el estado de portador de los diferentes serotipos. La vacuna neumocócica polisacárida 23 valente (PPV23) induce una respuesta inmune T independiente que es de corta duración y no previene la colonización. Por el contrario las vacunas conjugadas 10 valente (PCV10V) y 13 valente (PCV13) generan una inmunidad T dependiente que si reduce la colonización por los serotipos incluidos en su composición. Por este motivo las vacunas conjugadas proporcionan inmunidad de grupo. La vacunación de adolescentes frente a Neisseria menigintidis puede modificar el patrón de transmisión de la infección con una reducción de la incidencia en niños. En la actualidad se dispone de vacunas conjugadas frente a meningococo C, conjugadas tetravalantes frente a los serogrupos ACWY y de proteínas recombinantes frente a meningococo B. La inmunidad de grupo generada por vacunas conjugadas ha sido demostrada para Neisseria menigintidis C. Desafortunadamente existe escasa evidencia del impacto de las vacunas frente a meningococo B en la reducción del estado de portador entre adultos jóvenes. La infección natural por Bordetella pertussis estimula la producción de linfocitos T de memoria e induce una intensa respuesta de IgA secretora en la nasofaringe. En contraste con la infección natural y con las vacunas de células completas las actuales vacunas acelulares, no generan inmunidad en mucosas y no otorgan inmunidad de grupo. En un intento de resolver este problema se están desarrollando vacunas alternativas frente a Bordetella pertussis como las nuevas de células completas y las vivas atenuadas.

Assessment of humoral and cell-mediated immune responses to pertussis vaccination: a systematic review protocol

INTRODUCTION

Globally, some studies show a resurgence of pertussis. The risks and benefits of using whole-cell pertussis (wP) or acellular pertussis (aP) vaccines in the control of the disease have been widely debated. Better control of pertussis will require improved understanding of the immune response to pertussis vaccines. Improved understanding and assessment of the immunity induced by pertussis vaccines is thus imperative. Several studies have documented different immunological outcomes to pertussis vaccination from an array of assays. We propose to conduct a systematic review of the different immunological assays and outcomes used in the assessment of the humoraland cell-mediated immune response following pertussis vaccination.

METHODS AND ANALYSIS

The primary outcomes for consideration are quality and quantity of immune responses (humoral and cell-mediated) post-pertussis vaccination. Of interest as secondary outcomes are types of immunoassays used in assessing immune responses post-pertussis vaccination, types of biological samples used in assessing immune responses post-pertussis vaccination, as well as the types of antigens used to stimulate these samples during post-pertussis vaccination immune response assessments. Different electronic databases (including PubMed, Cochrane, EBSCO Host, Scopus and Web of Science) will be accessed for peer-reviewed published and grey literature evaluating immune responses to pertussis vaccines between 1990 and 2019. The quality of included articles will be assessed using standardised risk and quality assessment tools specific to the study design used in each article. Data extraction will be done using a data extraction form. The extracted data will be analysed using STATA V.14.0 and RevMan V.5.3 software. A subgroup analysis will be conducted based on the study population, type of vaccine (wP or aP) and type of immune response (cell-mediated or humoral). Guidelines for reporting systematic reviews in the revised 2009 Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement will be used in this study.

ETHICS AND DISSEMINATION

Ethics approval is not required for this study as it is a systematic review. We will only make use of data already available in the public space. Findings will be reported via publication in a peer-reviewed journal and presented at scientific meetings and workshops.

TRIAL REGISTRATION NUMBER

CRD42018102455.

Pertussis: New preventive strategies for an old disease

In the last twenty years, despite high vaccination coverage, epidemics of pertussis are occurring in both developing and developed countries. Many reasons could explain the pertussis resurgence: the increasing awareness of the disease, the availability of new diagnostic tests with higher sensitivity, the emergence of new Bordetella pertussis (B. pertussis) strains different from those contained in the current vaccines, the asymptomatic transmission of B. pertussis in adolescents and adults and the shorter duration of protection given by the acellular pertussis (aP) vaccine. New preventive strategies have already been implemented, such as booster doses of aP vaccine in adolescents and adults, maternal immunisation during pregnancy and the "cocooning" strategy, but more are still needed. Knowing what is new about this old disease is necessary to reduce its incidence and to protect infants too young to be vaccinated, which have the highest risk of complications and death.

Multicenter Clinical Evaluation of the Automated Aries Bordetella Assay

Molecular methods offer superior sensitivity and specificity and reduce testing turnaround time from days to hours for detection of Bordetella pertussis and Bordetella parapertussis In this study, we evaluated the performance of the automated PCR-based Aries Bordetella Assay, which detects both B. pertussis and B. parapertussis directly from nasopharyngeal swab specimens. The limits of detection (LoDs) were 1,800 CFU·ml^-1 for B. pertussis and 213 CFU·ml^-1 for B. parapertussis The assay detected 16/18 unique B. pertussis/B. parapertussis strains. Of 71 potentially cross-reacting organisms, 5 generated false positives in 1/6 replicates; none of 6 additional Bordetella spp. were erroneously detected. Specimens were stable at 20 to 25°C for at least 10 h, at 4 to 8°C for 10 days, and at temperatures not exceeding -70°C for 6 months. Of 1,052 nasopharyngeal specimens from patients with suspected pertussis, 3.0% (n = 32) were B. pertussis positive and 0.2% (n = 2) were B. parapertussis positive. Combining these data with Aries Bordetella Assay data from 57 nasopharyngeal samples with previously confirmed B. pertussis or B. parapertussis data and with data from 50 contrived B. parapertussis samples, the proportions of positive and negative agreement of the respective Aries assays with the reference assays were 97.1% and 99.0% for B. pertussis and 100% and 99.7% for B. parapertussis The Aries Bordetella Assay provides accurate detection and distinction of B. pertussis and B. parapertussis infections within 2 h. (This study has been registered at ClinicalTrials.gov under registration no. NCT02862262.).

Economic evaluation of adolescents and adults' pertussis vaccination: A systematic review of current strategies

The reemergence of pertussis in the last two decades led to the introduction of adolescents and adults immunization strategies of tetanus–diphtheria–acellular pertussis vaccines (Tdap) in several countries. The health authorities must consider economic aspects when deciding to recommend and fund new programs. Here we present a systematic review of worldwide full economic evaluations of pertussis vaccination targeting adolescents or adults published from 2000. Studies were identified by searching MEDLINE, Excerpta Medica, CRD, and Lilacs databases. Twenty-seven economic evaluations of different strategies with Tdap were identified. Booster vaccination for adolescents and adults were the most frequent, followed by cocooning and pregnant women vaccination. Strategies performance varied considerably among different studies. Assumptions regarding underreporting correction, herd protection and vaccine coverage were crucial to cost-effectiveness results. Understanding the model and the parameters used is essential to understand the results, and identify the major issues important to public health decisions.

Prevention of pertussis: An unresolved problem

Pertussis is a highly contagious respiratory disease caused by Bordetella pertussis. However, after the introduction of the whole-cell pertussis vaccine (wP), the annual incidence rates of the disease progressively declined. Despite this result, the inclusion of wP in the national immunization schedule of infants and young children was debated regarding its safety. Several efforts to produce vaccines based on B. pertussis components capable of evoking protective immunity with no or limited adverse events were made. Of these others, five pertussis antigens were considered possible components of acellular vaccines (aPs): pertussis toxin (PT), filamentous haemagglutinin (FHA), pertactin (PRN) and fimbria proteins 2 and 3. However, the introduction of aPs was followed by a slight but progressive increase in the incidence of pertussis. This paper discusses the potential reasons for reduced aPs efficacy. Moreover, it attempts to evaluate the real effectiveness of aPs and the potential differences between available preparations. Data analysis showed that several boosters are needed to maintain protection against pertussis and additional studies are needed to confirm the antigens that should be included in aPs to improve the prevention of pertussis.

Development of a thermostable spray dried outer membrane vesicle pertussis vaccine for pulmonary immunization

Worldwide resurgence of whooping cough calls for improved, next-generation pertussis vaccines that induce broad and long-lasting immunity. A mucosal pertussis vaccine based on outer membrane vesicles (omvPV) is a promising candidate. Further, a vaccine that is stable outside the cold chain would be of substantial advantage for worldwide distribution and application. A vaccine formulated as a powder could both stabilize the vaccine as well as make it suitable for pulmonary vaccination. To that end, we developed a spray dried omvPV with improved stability compared to the liquid omvPV formulation. Spray drying did not affect the structural integrity of the omvPV. The antigenicity of Vag8, a major antigen in omvPV was diminished slightly and an altered tryptophan fluorescence indicated some changes in protein structure. However, when administered via the pulmonary route in mice after reconstitution, spray dried omvPV showed comparable immune responses and protection against challenge with live B. pertussis as liquid omvPV. Mucosal IgA and Th17 responses were established in addition to broad systemic IgG and Th1/Th17 responses, indicating the induction of an effective immunity profile. Overall, a spray dried omvPV was developed that maintained effective immunogenic properties and has an improved storage stability.

Pertussis and Rotavirus Vaccines - Controversies and Solutions

Pertussis and rotavirus vaccines have been the subject of several controversies over the years. In this paper the authors discuss facts and myths behind these controversies and also suggest solutions to overcome some limitations of these vaccines. The whole-cell pertussis vaccine (wPV) came into disrepute due to the associated adverse reactions, resulting in its replacement by acellular pertussis vaccine (aPV) in industrialized nations in 1990s. Although wPV is known to have more side effects; but they are usually minor. Whole-cell pertussis containing vaccine is being used safely in the National Immunization programme in India from many years. Another controversy erupted during 2009-2010, when there were reports of resurgence of pertussis cases among adolescents and adults, from developed nations. Present literature review raises doubts about long term protection offered by aPV, when compared with wPV. In spite of prevailing controversy, acellular pertussis containing vaccines should be acceptable, if timely delivery of primary and booster doses is ensured; including vaccination of adolescents and pregnant women. Initial rotavirus vaccine was withdrawn from the market because of increased risk of intussusception. Although three new generation rotavirus vaccines are currently available for use in India, but doubts about their efficacy, long term protection and safety still exists. Present literature review found them to be safe and moderately efficacious because of reasonable good cross protection. Even a moderately efficacious vaccine like rotavirus vaccine could significantly improve the outcome if disease burden is high. Therefore, it is being included in National Immunization Programme of India.