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Recently, transformerless (TL) inverters are being extensively used in small-scale photovoltaic (PV) systems due to their compact-size, lighter-weight, lower-cost and higher-efficiency compared to their counterpart with transformer. However, the growing penetration of these small-scale based PV systems and low-inertia induction motor (IM) loads in low-voltage distribution networks (DNs) make the grid more vulnerable to short-term voltage stability (STVS). Hence, this paper thoroughly examines the STVS of DN with high-penetration of TL-PV units, and provides countermeasures by TL-PV systems to mitigate any short-term voltage instability. The detailed dynamic model of the TL inverter is developed first. Next, three control strategies: (1) constant peak current (CPC), (2) constant active current (CAC), and (3) constant active power (CAP) with low voltage ride through (LVRT) and dynamic voltage support (DVS) capabilities are proposed to improve STVS. The impacts of different level of PV penetrations and LVRT capability of TL-PV inverters on the STVS are explored. Moreover, countermeasures, such as LVRT with CAC and CAP controls and DVS by the TL-PV systems are designed and implemented. Several case studies are carried out on an IEEE 4 bus system first, and later extended to IEEE 13 node test feeder. The results show that DVS can further improve STVS in residential DNs. In addition, CAP and CAC control strategies can speed-up the postdisturbance voltage recovery compared with the conventional CPC control. [ABSTRACT FROM AUTHOR]

Eggplant or brinjal (Solanum melongena) is a popular vegetable grown throughout Asia where it is attacked by brinjal fruit and shoot borer (BFSB) (Leucinodes orbonalis). Yield losses in Bangladesh have been reported up to 86% and farmers rely primarily on frequent insecticide applications to reduce injury. Bangladesh has developed and released four brinjal varieties producing Cry1Ac (Bt brinjal) and is the first country to do so. We report on the first replicated field trials comparing four Bt brinjal varieties to their non-Bt isolines, with and without standard insecticide spray regimes. Results of the two-year study (2016–17) indicated Bt varieties had increased fruit production and minimal BFSB fruit infestation compared with their respective non-Bt isolines. Fruit infestation for Bt varieties varied from 0–2.27% in 2016, 0% in 2017, and was not significantly affected by the spray regime in either year. In contrast, fruit infestation in non-Bt lines reached 36.70% in 2016 and 45.51% in 2017, even with weekly spraying. An economic analysis revealed that all Bt lines had higher gross returns than their non-Bt isolines. The non-sprayed non-Bt isolines resulted in negative returns in most cases. Maximum fruit yield was obtained from sprayed plots compared to non-sprayed plots, indicating that other insects such as whiteflies, thrips and mites can reduce plant vigor and subsequent fruit weight. Statistically similar densities of non-target arthropods, including beneficial arthropods, were generally observed in both Bt and non-Bt varieties. An additional trial that focused on a single Bt variety and its isoline provided similar results on infestation levels, with and without sprays, and similarly demonstrated higher gross returns and no significant effects on non-target arthropods. Together, these studies indicate that the four Bt brinjal lines are extremely effective at controlling BFSB in Bangladesh without affecting other arthropods, and provide greater economic returns than their non-Bt isolines. [ABSTRACT FROM AUTHOR]

The conventional technique of harvesting free non-vascularized fibular grafting is associated with different scale of morbidity and usually a long scar. We follow a technique that causes minimum interference to the surrounding soft tissues to harvest the desired length of fibula. This prospective study was performed at Department of Orthopaedics, Dhaka Medical College Hospital from January 2018 to December 2018. Thirty patients of average age 10.5 years (range 8 to 14 years) were taken up for the study. The fibula was harvested by two separate incisions, 1 cm each at proximal and distal extent of proposed length of graft after elevating the periosteum circumferentially using a periosteum elevator. Compression bandage and above knee plaster immobilization was applied that help to reduce hematoma formation. The mean follow up is 12 months. The patients were evaluated clinically and by radiology. Twenty nine patients showed good results. One patient had delayed wound healing resulting in fair result. This modified approach of harvesting fibula reduces donor site morbidity and is safer and easier than conventional approach.

Low-income countries (LICs) and lower-middle-income countries (LMICs) are still deprived of the optimum doses of coronavirus disease 2019 (COVID-19) vaccines for their population, equal access and distribution, as well as mass immunization roadmaps to be implemented for achieving herd immunity and protection from the ongoing pandemic. In this short report, we are interacting with the world public health experts, as well as national and global leaders for warranting the mass vaccination drive to be more progressive against COVID-19 with equitable access of vaccines to LICs or LMICs to save the lives of the poorest country people and refugees. From several scientific databases, such as Google Scholar, PubMed, as well as national and international news websites, the data were collected data by utilizing appropriate keywords regarding the topic. Bangladesh might be exemplified in this brief communication as the representative of LMIC. As of October 14, 2021, 48% of the world's people have received at least one dose of the COVID-19 vaccine. In contrast, only 2.5% of people from LICs have come in under COVID-19 vaccination for at least a single shot. Both LICs and LMICs need far more vision and ambition, including political, administrative, and diplomatic progress along with enhancing the vaccination drive for their population to be immunized through simultaneous mass vaccination progress of other countries with implementing public health safety measures against the COVID-19 pandemic.

Background: Here, we have shortly reported the recent updates on the disastrous progressions of the deadly delta variant and a virulent coinfection or post-COVID-19 infection of black fungus in India and its neighbouring countries., Methodology: We searched by utilizing appropriate keywords in Google Scholar, PubMed and other scholarly databases alongside several national and international newspapers to collect the latest data regarding the targeted topic., Results: Recently, the delta variant is wreaking havoc in India, UK, and other countries around the globe and has also exhibited successful infections in around 20 to 55% of the people who have already recovered from COVID-19 originating from the different strains. Besides, a significant catch is the prevalence of 85.5% and 64.11% of Mucormycosis infections being co-morbid with COVID-19 and diabetes, respectively in South-Asian regions., Conclusions: To avert the emergence of an epidemic amid the pandemic, prompt actions from concerned authorities are warranted. Proper education on black fungus infection and associated risks from the COVID-19 and diabetes, adequate public awareness, and sufficient healthcare assistance to battle such fungal infections effectively should be ensured as quickly as possible., (© 2021 Elsevier Masson SAS. All rights reserved.)

Healthcare professionals are the crucial and influencing source of information for vaccines and their communication among patients and communities that can accelerate successful vaccination in a country. This cross-sectional study was one of the first and foremost ones in Bangladesh to observe the basic perception and attitudes towards vaccination against COVID-19 among the healthcare workers (HCWs) - doctors, interns, nurses, ward boys, cleaners, and medical technologists of major COVID-dedicated hospitals. The cross-sectional questionnaire-based study was conducted in February 2021 among 550 HCWs to assess the perception and attitude towards vaccination against COVID-19. The study participants were targeted as the priority group for COVID-19 vaccination, working in two major COVID-dedicated hospitals, Holy Family Red Crescent Medical College Hospital (HF-center), and Sheikh Russel National Gastro-liver Institute and Hospital (SR-center) in Dhaka, Bangladesh during the pandemic. The questionnaire was structured with a three-point scale of responses from 'true', 'false', and 'do not know'. The responses were calculated on point-score as +1 for the correct response, -1 for the wrong response, and 0 for 'do not know' with an overall highest and the lowest possible score of +5 to -5. Absolute (n) and relative frequencies (%) were presented for qualitative variables, while quantitative variables were presented as mean (± standard deviation). Chi-square test was done for univariate analysis of qualitative variables and Student's t-test for quantitative variables. With the 95.27% response rate, including 204 males and 320 were female and the male: female ratio was 1: 1.56. The majority of the participants were doctors (45.8%) followed by nurses (27.9%), and MLSS (26.3%) respectively. The respondents were between 18 to 64 years of age with a mean of 36.17±10.94 years. Most of the respondents (95.99%) responded correctly about the cost-free availability of a vaccine against COVID-19 in the country, 87.40% preferred vaccination as safe and effective. Again 29.77% HCWs think the vaccine might not be safe or effective due to emergency authorization. Only 38.93% of respondents could respond correctly about the necessity of vaccines for children, 31.10% think the vaccination was not required instead of natural immunity. The positive perception and attitude of the frontline HCWs in COVID-dedicated hospitals in Bangladesh are crucial which will positively influence motivation and wide acceptance among the general population for the attainment of the nationwide vaccination program, and adopt effective strategic modification to minimize the gaps for a low-middle income country like Bangladesh with its resource constrain.

Noxious stimuli during craniotomy may encourage hypertension and tachycardia, which may rise to morbidity in patients with intracranial hypertension. After craniotomy a moderate level of postoperative pain observed. The objective of this study was to observe the effect of intravenous paracetamol with bupivacaine scalp nerve block (SNB) on haemodynamics response as well as anaesthetic & analgesic requirements during supratentorial craniotomies. This is a single-blind, placebo-controlled, randomized clinical trial carried out in the Neurosurgery operation theatre from August 2015 to July 2017 under supervision of Department of Anaesthesia, Analgesia and Intensive Care Medicine of Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh. A total of 40 patients aged 18-60 years with supratentorial space occupying lesion undergoing craniotomy under general anaesthesia who were attended in the department of Neurosurgery, BSMMU were enrolled in this study and they were divided randomly into two groups, 20 patients in each. The Group A received 100ml normal saline infusion and 0.25% bupivacaine (20ml) in scalp block, while the Group B received intravenous injection paracetamol (1gm) and 0.25% bupivacaine (total 20ml) in scalp block. Statistical analyses were obtained Statistical Packages for Social Sciences (SPSS-22). The mean systolic blood pressure varied within the normal range in both groups. The mean DBP of Group B remained significantly lower than that of Group A in different follow up except at 30 minutes and 60 minutes after dura incision. However, mean MAP of Group B remained significantly lower than that of Group A in different time interval. The mean heart rate of Group B remained significantly lower than that of Group A. The mean intraoperative propofol as well as fentanyl requirements were significantly decreased in Group B in comparison to Group A. The combination of intravenous paracetamol with bupivacaine scalp nerve block provides better intra-operative haemodynamic stability and neurosurgical compliances for the patients undergoing supratentorial craniotomies under general anaesthesia.

Background: We performed the first epidemiologic investigation to examine association of demographics and clinical characteristics at diagnosis, as well as health care expense coverage, with survival of US children with aplastic anemia (AA)., Methods: We obtained electronic medical record data of 1140 children aged 0-19 years diagnosed with AA followed at a pediatric health system between 2004 and 2014. Kaplan-Meier curve and Cox proportional hazards regressions were used., Results: Self-pay patients had a mortality risk five times higher than that of those insured by publicly funded insurance (hazards ratio, 95% CI: 6.0, 3.7-9.8). Other features associated with higher mortality risk include pancytopenia (hazards ratio, referent: 4.2, constitutional AA); underweight (2.0, normal-weight); platelet count <50 × 109/l (1.3, ≥50 × 109/l); male sex (1.3, female); and ages at diagnosis 6-11, 11-16 and 16-19 years (1.6, 1.9, 2.3, 1-3 years), respectively., Conclusions: Self-pay was the strongest prognostic factor for pediatric AA mortality. Older age, pancytopenia, underweight, male sex and lower platelet count were also associated with increased risk of mortality. These findings may be useful for providers, researchers and policymakers to ensure effective health care delivery to this population and to motivate future etiologic research and establishment of a surveillance registry., (© The Author(s) 2018. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The purpose of this article is to provide information on the history, accomplishments, and future direction of the Bt brinjal (eggplant) program in Bangladesh, formerly under the Agricultural Biotechnology Support Project II, now the South Asia Eggplant Improvement Partnership (SAEIP). The India-based Maharashtra Hybrid Seed Company (Mahyco) developed an eggplant expressing Cry1Ac (EE-1) for control of the eggplant fruit and shoot borer (EFSB). In a partnership among Mahyco, USAID, Sathguru Management Consultants and Cornell University EE-1 was provided to the Bangladesh Agricultural Research Institute (BARI) who bred it into local varieties. After regulatory approval, four varieties were distributed to 20 farmers who harvested Bt brinjal in 2014. Adoption in subsequent years has increased rapidly so that, in 2018, 27,012 farmers used this technology. This article provides background information on the process leading up to current adoption levels, the level of control of EFSB achieved and the economic benefits of Bt brinjal. Efforts on stewardship, farmer training and communication are discussed. In order to ensure the long-term future of the partnership, we discuss the need to enhance involvement of the private sector in the production and stewardship of Bt eggplant. Bt brinjal is the first genetically engineered crop to be commercially released in Bangladesh, and other GE crops are in the pipeline. Hence, success of the Bt brinjal partnership is likely to affect the future of other GE crops in Bangladesh, as well as other parts of the world where biotechnology is needed for food security and environmental safety.

Objective: There is limited data characterizing the risk and impact of surgical site infection (SSI) in neonates; this makes it difficult to identify factors that increase neonatal SSI risk and to determine how SSI affects outcomes in this special population., Study Design: The American College of Surgeons National Surgical Improvement Program Pediatric (NSQIP-P) collected data on children undergoing surgery at children's hospitals from 2012 to 2014. Neonates undergoing general surgical procedures were characterized with regard to demographic characteristics and comorbidities. Perioperative variables such as wound class, type of surgery and length of operation were also evaluated., Results: Seven thousand three hundred and seventy-nine neonates were identified in the NSQIP-P participant user file. The overall SSI rate was 2.6%. Only wound class and length of surgery were significantly associated with SSI. Furthermore, SSI was independently associated with longer length of stay, even after adjusting for covariates., Conclusions: This is the largest study to date analyzing SSI in neonates. We found that perioperative variables have a more significant impact on SSI than patient factors, suggesting that operation-related characteristics are influencing SSI. Furthermore, neonates with SSI are more likely to have prolonged hospitalizations even after adjusting for patient comorbidities.

Tuberculosis (TB) isolated in Common Bile Duct (CBD) is very rare and its treatment is somewhat controversial. We report a case of distal CBD tuberculosis diagnosed as cholangiocarcinoma. A 40 year old man presented with obstructive jaundice without abdominal pain, fever or weight loss. Ultrasonography and Magnetic Resonance Cholangio-Pancreatography (MRCP) indicated a mass lesion in the Distal CBD, which caused structure of the distal common bile duct. As Cholangiocarcinoma was suspected, he underwent Whipple procedure (pancreaticoduodenectomy). Histological examination of resected specimen revealed typical features of tuberculosis in the distal CBD, pancreatic head and lymph nodes. The rest of the abdominal cavity was unremarkable. Anti-microbial therapy for tuberculosis is started for 12 month course and he is well.

Four Aeromonas strains from clinical and environmental samples differed from known species on the basis of rpoD gene sequence. Multilocus phylogenetic analysis and in silico DNA-DNA hybridization confirmed them as four new species even though their 16S rRNA gene sequence similarity with their closest relatives was >98.7%, as occurred for other Aeromonas spp.

Drinking raw date palm sap is the primary route of Nipah virus (NiV) transmission from bats to people in Bangladesh; subsequent person-to-person transmission is common. During December 2010 to March 2011, we investigated NiV epidemiology by interviewing cases using structured questionnaires, in-depth interviews, and group discussions to collect clinical and exposure histories. We conducted a case-control study to identify risk factors for transmission. We identified 43 cases; 23 were laboratory-confirmed and 20 probable. Thirty-eight (88%) cases died. Drinking raw date palm sap and contact with an infected person were major risk factors; one healthcare worker was infected and for another case transmission apparently occurred through contact with a corpse. In absence of these risk factors, apparent routes of transmission included drinking fermented date palm sap. For the first time, a case was detected in eastern Bangladesh. Identification of new epidemiological characteristics emphasizes the importance of continued NiV surveillance and case investigation.

Amoebic liver abscess is a common condition in Bangladesh. Though conservative treatment plays a major role, refractory patients can be successfully treated with minimally invasive approach. This prospective study was carried out to evaluate the prospect of sono-guided percutaneous catheter drainage for liver abscess patients not responding to conservative treatment. This study was done at Dhaka Medical College Hospital from January 2005 to June 2006 among patients with liver abscess that were treated conservatively outside and got admitted in different surgery and medicine units. Included 35 patients were evaluated clinically and through relevant investigations. Sono-guided percutaneous pigtail catheter was introduced for drainage and patients were followed up for two weeks on average at hospital indoor by amount of drainage, clinical improvement and serial follow up USG. After discharge from the hospital, all patients were followed up monthly and assessed clinically and ultrasonographically up to two months on outdoor basis. Thirty five patients underwent pigtail catheter drainage that was refractory to conservative treatment or needle aspiration. Following insertion of catheter patients who were pyrexic, fever subsided in two to three days and never back during the postoperative period and follow up. Antimicrobials were changed according to the report of the culture and sensitivity of the aspirate that was done routinely. Maximum total (4300 ml) amount of pus was drained in a patient. Average duration of catheter drainage in this study was 8 days. With a very low morbidity and zero mortality rates, minimum treatment costs and early return to regular life style proved this minimally invasive procedure to be a rational treatment option for amoebic liver abscess in selective cases.

This paper explores the utility of cluster- and case-based surveillance established in government hospitals in Bangladesh to detect Nipah virus, a stage III zoonotic pathogen. Physicians listed meningo-encephalitis cases in the 10 surveillance hospitals and identified a cluster when ⩾2 cases who lived within 30 min walking distance of one another developed symptoms within 3 weeks of each other. Physicians collected blood samples from the clustered cases. As part of case-based surveillance, blood was collected from all listed meningo-encephalitis cases in three hospitals during the Nipah season (January-March). An investigation team visited clustered cases' communities to collect epidemiological information and blood from the living cases. We tested serum using Nipah-specific IgM ELISA. Up to September 2011, in 5887 listed cases, we identified 62 clusters comprising 176 encephalitis cases. We collected blood from 127 of these cases. In 10 clusters, we identified a total of 62 Nipah cases: 18 laboratory-confirmed and 34 probable. We identified person-to-person transmission of Nipah virus in four clusters. From case-based surveillance, we identified 23 (4%) Nipah cases. Faced with thousands of encephalitis cases, integrated cluster surveillance allows targeted deployment of investigative resources to detect outbreaks by stage III zoonotic pathogens in resource-limited settings.

Three groups of Aeromonas strains isolated from Finland lakes experiencing cyanobacterial blooms could not be assigned to any known species of this genus on the basis of 16S rRNA and rpoD gene sequences. The Multilocus Phylogenetic Analysis (MLPA) of the concatenated sequence of seven genes (gyrB, rpoD, recA, dnaJ, gyrA, dnaX and atpD; 4093bp) showed that the three groups of strains did not cluster with any known Aeromonas spp. and formed three independent lineages. This was confirmed by performing the analysis with their closest relatives using 15 genes (the latter 7 and cpn60, dnaK, gltA, mdh, radA, rpoB, tsf, zipA; 8751bp). Furthermore, ANI results between the genomes of the type strains of the three potential new species and those of their close relatives were all <96% which is the previously proposed cutoff value for differentiating species within this genus. The in silico DDH values of the three type strains of the new species also showed a similarity<70% with the most closely related species indicating they belong to different taxa. The three groups of strains could be differentiated from each other and from other known Aeromonas species on the basis of several phenotypic characters. This polyphasic study revealed that the 3 groups of strains represent 3 novel Aeromonas species for which the names Aeromonas aquatica sp. nov. (type strain AE235T=CECT 8025T=LMG 26712T), Aeromonas finlandiensis sp. nov. (type strain 4287DT=CECT 8028T=LMG 26709T) and Aeromonas lacus sp. nov. (type strain AE122T=CECT 8024T=LMG 26710T) are proposed., (Copyright © 2015 Elsevier GmbH. All rights reserved.)

Primary malignant melanoma of penis with secondaries to the adrenal gland is rare. Here we report a case of malignant melanoma of penis in a 60 years old man who presented with intermittent gross, episodic haematuria of 11 months duration and a hard indurated pigmented fungating lesion over the glans penis. Following an initial tissue biopsy from the penile growth which revealed malignant melanoma the patient underwent partial Panectomy. Few days after recovery the patient underwent laparotomy and incisional biopsy from adrenal mass revealed metastatic malignant melanoma histopathologically.

Objectives: The objective of this study is to explore the magnitude and pattern of electrical injury in Bangladesh., Method: A national survey was conducted between January and December 2003 in Bangladesh. Nationally representative data were collected from 171,366 rural and urban households comprising a 819,429 population. The survey was conducted at a household level with a structured questionnaire., Results: The incidence of fatal and non-fatal injury was found to be 1.6 and 73.7 per 100,000 population year respectively. Compared to females, males were found at a higher risk (RR 1.62; 95% CI 1.37-1.91) and rural people found more vulnerable compared to urban people (RR 5.97; 95% CI 4.71-7.57). The home was found as the most common place for electrical injury, with more than 50% of injury taking place at home. The household source of electricity was found as the most common source of electrical injury. Lightning was also found as major source for electrical injury which constituted more than 25% of the injuries cause by electrical current. More than 80% of electrical injuries occurred between 6a.m. and 6p.m., Conclusion: Electrical injury is an emerging cause of mortality and morbidity in both urban and rural areas of Bangladesh. Males and rural people were the more vulnerable group for electrical injury compared to women and the urban population. The home is the most common place for injury occurrence., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Aims: To identify and characterize bacteriophages specific for Edwardsiella ictaluri, the causative agent for enteric septicemia of catfish (ESC)., Methods and Results: Two bacteriophages were isolated that infect Edw. ictaluri. They both produce clear plaques, have icosahedral heads with a non-rigid tail, and are tentatively classified as Siphoviridae. Phages PhieiDWF and PhieiAU are dsDNA viruses with approximate genome sizes of 40 and 45 kb, respectively. The addition of 500 micromol l(-1) CaCl(2) enhanced phage titres. Both phages have a latent period of 40 min and an estimated burst size of 270. Every Edw. ictaluri strain tested was susceptible to phage infection with variable plaquing efficiencies and with no evidence of lysogeny, with no plaques detected on other bacterial species., Conclusions: Two unique bacteriophages were isolated that show host-specificity for Edw. ictaluri, have temperature and metal cation-dependent infectivity, and are tentatively placed within the family Siphoviridae., Significance and Impact of the Study: This is the first report of bacteriophages specific to Edw. ictaluri, an important fish pathogen affecting farm-raised channel catfish. Initial characterization of these bacteriophages has demonstrated their potential use as biotherapeutic and diagnostic agents associated with ESC.

Knockout of the interleukin-18 (IL-18) gene predisposed mice to impaired clearance of neurovirulent influenza A virus-infected neurons from the brain. In wild-type mice, IL-18 molecule-producing microglia/macrophages emerged in virally attacked regions as early as day 3 after infection. Microglial transformation into macrophages culminated at day 7 to 9, with upregulated expression of Iba1, a novel calcium-binding protein that controls phagocytic functions of microglia/macrophages. In IL-18-/- mice, microglial transformation was interrupted with reduced Iba1 expression. Interferon-gamma (IFN-gamma)-immunopositive neurons appeared in and around virally invaded regions in wild-type mice, peaking in number at day 7, whereas such cells were barely detected in IL-18-/- mice. Stereotaxic microinjection of recombinant IFN-gamma triggered microglial transformation in IL-18-/- mice and upregulated Iba1 expression, leading to effective eradication of virally infected neurons. Collectively, these results suggest that IL-18 plays a key role in activating microglial functions directed against the influenza virus infection by inducing neuronal IFN-gamma in the brain parenchyma., (Copyright 2001 Academic Press.)

The senescence-accelerated mouse (SAM) strain P1, which has a short life span, was adopted as a murine model for an investigation of the pathogenesis of viral infection in elderly adults. After intranasal inoculation with influenza A virus, the SAM-P1 mice showed a higher rate of mortality, with prolonged virus growth in the lungs. The increased susceptibility was associated with impaired activity of both NK cells and virus-specific cytotoxic T lymphocytes. The production of interferon-gamma and interleukin-12 was significantly restrained, which suggests a partial deficiency of the T helper (Th) 1 cells. In contrast, the immunologic activity of the Th2 cells appeared to be functionally normal, judging from the release of large amounts of interleukin-4 followed by production of appropriate amounts of influenza virus-specific antibody. It is suggested that the elicitation of cellular immunity is an important and effective procedure for protecting the elderly from influenza virus infection.

Infection of mice with the egg-adapted (EA) strain of influenza virus was studied as a murine model of human live attenuated virus vaccine. The growth and spread of the EA virus in the mouse lungs were restricted, and only small inflammatory changes were detected in the respiratory tracts. Deletion and substitutions of amino acids were found in the hemagglutinin molecule of the EA virus, which were attributable to the reduced envelope fusion activity in virus multiplication cycles. Intranasal inoculation of mice with the EA virus induced specific IgG and IgA antibody production together with a specific cytotoxic T lymphocyte response. Immunized mice showed a distinct resistance to subsequent lethal challenge with the virulent influenza virus. These results indicate that the mutant virus loaded with a growth restriction in the respiratory tract is an appropriate candidate for a live attenuated vaccine.