Haemagglutination Inhibition Technique Research Articles

Serological Evidence of Arboviruses in Horses During West Nile Fever Monitoring Surveillance in Southeastern Brazil

Many human arboviruses are also pathogenic for horses, and some of these have emerged recently. A descriptive cross-sectional observational study was conducted to assess the prevalence of West Nile virus (WNV) and other arboviruses among 77 horses on the rural properties of the Espirito Santo state, Brazil. Serum samples were screened for arbovirus-reactive antibodies using the hemagglutination inhibition technique and subsequently a plaque reduction neutralization test for the confirmation of exposure from sera was used to detect heterotypic immune reactions. Overall, the total antibodies against at least one arbovirus of Alphavirus, Flavivirus, and Orthobunyavirus genera were detected in 39 (50.6%) animals. The antibodies to Phlebovirus were not detected in any sample. When the 24 WNV hemagglutination inhibition (HI)-positive samples were tested by the plaque-reduction neutralization test 90%, 9 (32.1%) were positive for WNV antibodies and 14 (50%) for Saint Louis encephalitis virus. Our findings indicate that the region provides ideal conditions for the emergence of arboviruses, reinforcing the need for further surveillance of mosquito-transmitted diseases in domestic animals.

Serological evidence of Eastern equine encephalitis circulation in equids in Pará state, Brazil.

Serum samples from 89 equids were analyzed (75 horses, 9 donkeys, and 5 mules) from the municipality of Viseu, Pará state, Brazil. Samples were collected in November 2014 and August 2015. The antibody prevalence against the following alphaviruses was estimated: Eastern equine encephalitis virus, Western equine encephalitis virus, Mucambo virus, and Mayaro virus. Seroprevalence was determined by the hemagglutination inhibition (HI) technique. Sera that exhibited HI antibodies with heterotypic reactions for the analyzed viruses were subjected to the 90% plaque reduction neutralization test (PRNT90). The HI prevalence of monotypic reactions to EEEV was 7.9%, and that of WEEV was 1.1%, as confirmed by PRNT90. Viral isolation attempts were negative for all tested blood samples. Our results suggest the circulation of equine encephalitis complex viruses. Future studies should evaluate the possible involvement of arthropod hosts and residents in the viral transmission in the study area.

Association of secretors and non-secretors in ABO blood group with incidence of rheumatic fever in south Indian population: An observational study

Background: The ABH secretors amongst blood groups are known to be associated with some bacterial infections. The prevalence of such secretors and association with incidence of rheumatic fever was studied in south Indian population. Aims/Objectives: To characterise the association of secretors and non-secretors in ABO Blood group with incidence of Rheumatic fever in south Indian population.Methodology: An observational study was conducted on 200 subjects, recruited by convenient sampling after meeting the inclusion and exclusion criteria. The procedure involved collection venous blood and unstimulated whole saliva samples, determination of ABO and Rh blood groups (agglutination method), evaluation of the secretor status (Haemagglutination Inhibition Technique) and Antistreptolysin O titre levels. The descriptive statistics were reported as frequencies and percentages while inferential statistics by chi-square or ANOVA test as needed.(p

Isolation and Identification Of New Sub-Genotypes Of Virulent ND Virus In Broiler Chickens In Qalybia Governorate.

A B S T R A C T Newcastle disease (ND) is a highly contagious disease causing huge economic losses to the poultry industry due to high morbidities and mortalities. This study was aimed to isolate and characterize the new sub-genotype NDV strains in Qalybia Governorate during 2017 and 2019. Sixty eight samples were collected from Sixty eight broiler chicken flocks suffering from high mortality reach to 80% with distinctive clinical signs and post-mortem lesions of NDV. NDV strains isolated through inoculation in specific pathogen free (SPF) eggs and were identified by hemagglutination (HA) and hemagglutiation inhibition(HI) techniques. There were 16/20 (about 80%) of selected suspected farm were positive for NDV With HI test . These hemagglutinating agents were confirmed as NDV strains through molecular characterization using one step RT-PCR targeting the partial F-gene of NDV. Sequencing and phylogenetic analysis were successfully performed with eight NDV isolates which possessed the motif 112 R/K-R-Q-K/RR116 at the C-terminus of the F2 protein and F (phenylalanine) at residue 117, indicating that they are velogenic genotype. The present study revealed the circulation of NDV class II genotype VII in Qalybia chicken flocks.

English

Inactivated oil based avian influenza vaccines are being used to confront viral outbreaks but seem to be ineffective due to the shorter life span of broiler birds. In such situations immunostimulating agents may play a vital role to overcome the problem. The current study was designed to investigate the co-stimulatory effect of levamisole on humoral response of chicken against inactivated oil based influenza vaccines in broiler birds. The efficacy of levamisole (LMS) hydrochloride, a standard immune modulator was evaluated on one hundred broilers in association with inactivated adjuvanted avian influenza vaccines. Avian influenza susceptible broilers were divided into nine groups, each having ten birds. The birds in groups G1, G2, G3, G5, G6 and G7 were offered 30 , 20 and 15mg kg-1 bwt levamisole for four consecutive days after being vaccinated with oil and gel based inactivated influenza vaccines respectively; birds in group G9 were kept as control. Whereas, birds in Group G4 were kept as oil base vaccinated control and Group G8 were kept as gel base vaccinated control without levamisole medication. Blood samples were obtained from wing vein on 14th, 28th and 36th days post vaccination. Anti-influenza antibody response was measured using haemagglutination inhibition (HI) technique.  Data analyzed by one way ANOVA and DMR test showed that levamisole in both regimens had appreciable effect on antibody titers (p<0.05). In conclusion, LMS can stimulate immune system which causes better response to vaccination. Further studies are needed to evaluate other effective factors for each of the best results of LMS. Key words: Levamisole, AIV H7N3, Immunomodulation. &nbsp

Seroprevalence of viral agents in vaquejada horses

In order to investigate the prevalence of viral diseases in vaquejada horses, samples were collected from Quarter Horse and Paint Horse breeds (males and females, aged between 2 and 15 years) from rural and urban areas of Mossoro, Rio Grande do Norte, Brazil were collected. The number of samples collected and tested varied with the techniques used: 132 serum samples were tested for vesicular stomatitis (VS) and equine viral arteritis (EVA), 118 for western and eastern equine encephalomyelitis (WEE/EEE), 114 for equine herpesvirus 1 (EHV-1), and 61 for equine influenza (EI). The techniques used varied according to the disease studied: tests for VS (Ribeirao and Alagoas strains), EVA, EHV-1, and WEE/EEE were performed using the seroneutralization technique in Vero cell cultures, while the test for for EI type-2 (H3N8) was performed using the hemagglutination inhibition technique. The following results were obtained: 39 (29.55%) and 6 (4.54%) VS-positive horses (n=132) harbored the Alagoas and Ribeirao strains, respectively; no animal tested positive for EVA (n=132); 11.01% (n=13) and 0.84% (n=1) animals tested positive for EEE and WEE (total n=118), respectively; and 22 out of 114 (19.29%) horses tested positive for EHV-1. The history of respiratory and reproductive diseases was statistically significantly (p = 0.02) related to the presence of antibodies against EHV-1. This is the first report of the seroprevalence of viral diseases in vaquejada horses in Rio Grande do Norte.

Prevalencia de anticuerpos contra virus de influenza equina en equinos deportivos de la República Argentina durante 2015 y 2016

Mediante un muestreo en dos etapas se analizó la población de equinos de deporte o recreación de toda la República Argentina que presenta una frecuencia regular (o alta) de movimien­tos y para los cuales la vacunación contra influenza equina es obligatoria. Mediante la técnica de inhibición de la hemaglutinación se evaluó la presencia de anticuerpos contra dos cepas del virus de la influenza equina: A/eq/2 La Plata 93 y A/eq/Argentina/E2345-1/2012. Los títulos obtenidos permi­tieron clasificar a los equinos en protegidos, parcialmente protegidos y no protegidos. El 57 % y el 59 % de los equinos fueron considerados como no protegidos contra la cepa La Plata 93 y Argentina 2012, respectivamente. El 34 % fue considerado como parcialmente protegido contra la cepa La Plata 93 y el 33 % contra la cepa Argentina 2012. Finalmente, el 9 % y el 8 % de los animales fueron considerados protegidos contra la cepa La Plata 93 y Argentina 2012, respectivamente. Se constató que los animales de mayor edad, con mayor cantidad de dosis de vacunas aplicadas y con la fecha de última vacunación más cercana a la fecha del muestreo, presentaron concentraciones mayores de anticuerpos. Menos del 10 % de los equinos tuvo títulos protectores y un alto porcentaje títulos inferiores a lo requerido para evitar la enfermedad, lo cual implica que existe en Argentina una gran cantidad de equinos que pueden diseminar la enfermedad sin presentar sintomatología.

Clinical and serological tests for arboviruses in free-living domestic pigeons (Columba livia).

BACKGROUND In this study, we evaluated the role of free-living domestic pigeons (Columba livia) as a reservoir of arboviruses in the city of Belém, state of Pará, Brazil. We investigated the presence of antibodies against the most prevalent arboviruses.OBJECTIVES This study was aimed at evaluating some clinical and physical parameters of domestic pigeons, including the presence of antibodies to Amazon-endemic arboviruses.METHODS Eighty-five healthy pigeons were captured in Mangal das Garças Park, in Belém, and were bled. Upon capture, the birds were subjected to a clinical examination in search of alterations that could indicate the presence of arboviruses. Blood samples were converted to serum and tested using the haemagglutination inhibition (HI) technique with a panel of 19 antigens of arboviruses circulating in the Amazon. The confirmation assay for the positive reactions to the viral species tested by HI was a neutralisation test in new-born Swiss albino mice (Mus musculus) [mouse neutralisation test (MNT)].FINDINGS A total of 10 (11.8%) serum samples tested positive for antiflavivirus antibodies by HI. All the samples positive for the HI test were subjected to MNT for detection of viruses and yielded negative results (logarithmic neutralisation index < 1.7).MAIN CONCLUSION The results represent the first serological detection of antiarbovirus antibodies in domestic pigeons as potential hosts of arboviruses in Brazil. The detection of haemagglutination-inhibiting antibodies against genus Flavivirus indicated that there was recent contact between the analysed domestic pigeons and these arboviruses. Further studies are needed to evaluate the role of free-living pigeons in the maintenance cycle and spread of arboviruses in the Amazon.

Serological Detection of Newcastle Disease Virus Antibodies in Local Chickens and Guinea Fowls in the Area of Kumasi, Ghana

Newcastle Disease (ND) has been identified as a major constraint to local poultry production with its impact being felt more in rural poultry production which forms about 80% of Ghana poultry population. However documented evidence on ND virus activity in rural poultry in Ghana is still lacking. Hence, this study was conducted to evaluate the level of circulating antibodies against ND using the Haemagglutination Inhibition (HI) technique. Sera collected from unvaccinated 292 chickens and 153 guinea fowls randomly selected from households and a live bird market in Kumasi and its environs were evaluated for Newcastle disease virus antibodies. Results showed 81.8 % (239/292) of local chickens and 24.2 % (37/153) of guinea fowls tested positive for ND antibodies. Comparison was made between the seroprevalence of ND antibodies in household and live bird market as well as between sexes. Significantly higher prevalence rate (p<0.05) was observed with chickens sampled from households compared to those from the live bird market. Higher ranges of titers were also observed in chickens from households than those from live bird markets. The presence of ND antibodies in these unvaccinated local chickens and guinea fowls indicated the presence of the virus amongst the rural poultry population, hence aneed for improvement in vaccine campaignand delivery against ND for rural poultry especially with the use of thermostable and improved oral or feed-based vaccine delivery systems.

Expression of the Gene Encoding Secretor Type Galactoside 2 &amp;lt;i&amp;gt;α&amp;lt;/i&amp;gt; Fucosyltransferase (&amp;lt;i&amp;gt;FUT&amp;lt;/i&amp;gt;2) and CD44 Marker in Urogenital Tumors

The aim of this work was to investigate the FUT2 gene, the secretor status and the expression of CD44 protein in epithelial cells obtain from saliva and urine samples from patients with urogenital tumours. We studied 104 subjects. Half of them had urogenital tumours, while the other half was the healthy control group. We determined the secretor status in saliva with the haemagglutination inhibition technique. We analyzed the FUT2 polymorphism by allele specific oligonucleotide–polymerase chain reaction (ASO-PCR) with specific primers for the G428 allele and the wild type allele of FUT2 gene. We found higher intensity of urogenital disease in the non-secretor group (OR = 3.44). In contrast with the healthy population, 51.6% of the patients with potential malignant urogenital lesions and cancerous lesions were non-secretors. We also investigate by confocal microscopy, the expression of CD44 protein in epithelial cells obtained from urine samples from these patients. The results obtained also showed fluorescence corresponding to the presence of CD44 protein in samples from patients diagnosed with cancer. Our study suggests that the lack of wild type FUT2 gene and a nonsecretor status appear to be an associated risk marker for the development of urogenital tumors. Several mechanisms, based on the properties of CD44 as the major hyaluronan CD44 in cell carcinomas receptor, have been proposed to explain the role of elevated CD44 expression during tumour development and progression. CD44 might be a good candidate as a predictor of prognosis in this group of cancers.

Evaluation of Seroconversion in Guinea Pigs Following Inoculation of New Formulations of Rubella Vaccine

Background and Aims: Rubella is a contagious viral disease mostly with mild clinical symptoms and often remains undiagnosed. Rubella infection may adversely affect pregnancy, especially in the first trimester and this mother to child transmission can cause congenital rubella and may be lead to permanent disability and mortality in children. Effective rubella vaccine should be prepared using suitable stabilizers. New stabilizers should be selected carefully in the manners that final product meet all requirements of stability, immunogenicity and safety. The aim of this study was to evaluate the immunogenicity of rubella vaccines that are formulated using two different new stabilizers in comparison to a commonly used vaccine that gelatin is used in it as a stabilizer. Materials and Methods: 28 guinea pigs were prospectively divided into four groups (one control and three test groups) according to the materials that they were subjected to receive, including the vaccines that formulated with hydrolyzed gelatin (G), Sorbitol (S) and Trehalose dehydrate (T) stabilizers. Control group was received sterile water for injection (WFI). Anti-rubella antibodies in the sera were measured using haemagglutination inhibition (HI) technique. The results were analyzed by Generalized Estimating equations (GEE) statistical test. Results: Our results showed that all three formulated vaccines (G, S and T) induced seroconversion in guinea pigs; however the vaccine that contained Trehalose dehydrate (T) induced a slightly higher level of antibody against rubella virus (p<0.01). Conclusion: As an important part of final bulk of rubella vaccines, stabilizers are continuously studied to achieve safer, more stable and more effective vaccines. In this study, the immunogenicity of newly formulated rubella vaccines (T&S) was comparable to the vaccines which formulated with routine stabilizer (G).

Effects of synbiotic on the intestinal morphology and humoral immune response in broiler chickens

The objective of this study was to investigate the effects of synbiotic on humoral response to Newcastle disease vaccine and intestinal morphology. A total of 108 one-d-old fast-growing broiler chickens (Ross 308) were allocated to pens, then, pens were assigned to 1 control and 2 treatments with 3 pens per treatment and 12 chickens per pen. Chickens were reared at standard condition for 6 week and provided a standard basal diet and diets supplemented with 0.1 or 0.2% synbiotic. On d 8, 22, 32, and 42, 12 chickens from each treatment were randomly selected and blood samples were collected. Antibody response was measured by the hemagglutination inhibition technique. On d 22, and 42, 12 chickens from each treatment were killed and 3 segments of intestine were dissected for evaluation of intestinal morphology. Antibody titers were increased in chickens fed the diet supplemented with synbiotic (P<0.05). Antibody level in chickens fed the diet supplemented with synbiotic increased at d 22, 32, and 42 compared to d 8. Amount of antibody was increased at d 32 compared to other day in chickens fed 0.2% synbiotic supplement (P<0.05). Antibody level was progressively reduced in the control group at d 22, 32, and 42. Duodenal villus height was greater in both treatments than their controls (P<0.05). Duodenal villus surface area was also greater in chickens fed 0.1% synbiotic supplement than controls at d 22, 32, and 42 (P<0.05). Jejunal villus width and surface area were lower in chickens fed 0.2% synbiotic supplement than controls on d 22 and 42 (P<0.05). Ileal villus height was lower (P<0.05) in chickens fed 0.2% synbiotic supplement than controls on d 42, while the villus width and surface area were only greater (P<0.05) in chickens fed the diet supplemented with 0.1% synbiotic. The sum of measured villus surface area in 3 intestinal parts was greater only in chickens fed 0.1% synbiotic supplement on d 42 (P<0.05). Villus types changed from leaf and tongue to convoluted and ridge shapes in both treatments on d 22 and 42 (ileum, 0.1 and 0.2% synbiotic) and 32 (jejunum, 0.2% synbiotic) compared to their controls (P<0.05). It is concluded that synbiotic had beneficial effects on antibody production, and antibody levels in chickens fed synbiotic supplement were maintained or increased during rearing. In intestine, only 0.1% synbiotic had positive effect on intestinal morphology.

Persistence of experimental Rocio virus infection in the golden hamster (Mesocricetus auratus)

Rocio virus (ROCV) is an encephalitic flavivirus endemic to Brazil. Experimental flavivirus infections have previously demonstrated a persistent infection and, in this study, we investigated the persistence of ROCV infection in golden hamsters (Mesocricetus auratus). The hamsters were infected intraperitoneally with 9.8 LD50/0.02 mL of ROCV and later anaesthetised and sacrificed at various time points over a 120-day period to collect of blood, urine and organ samples. The viral titres were quantified by real-time-polymerase chain reaction (qRT-PCR). The specimens were used to infect Vero cells and ROCV antigens in the cells were detected by immunefluorescence assay. The levels of antibodies were determined by the haemagglutination inhibition technique. A histopathological examination was performed on the tissues by staining with haematoxylin-eosin and detecting viral antigens by immunohistochemistry (IHC). ROCV induced a strong immune response and was pathogenic in hamsters through neuroinvasion. ROCV was recovered from Vero cells exposed to samples from the viscera, brain, blood, serum and urine and was detected by qRT-PCR in the brain, liver and blood for three months after infection. ROCV induced histopathological changes and the expression of viral antigens, which were detected by IHC in the liver, kidney, lung and brain up to four months after infection. These findings show that ROCV is pathogenic to golden hamsters and has the capacity to cause persistent infection in animals after intraperitoneal infection.

Seroprevalence of antibodies to the influenza A (H1N1) virus among healthcare workers prior to the 2009 pandemic peak

ObjectiveOur aim was to study the proportion of healthcare workers with a positive serology for Influenza A(H1N1)2009 without having flu, in a Spanish hospital at the beginning of the pandemic.MethodsA survey study carried out during August 2009 (before the peak of the pandemic in Spain) in the Hospital Costa del Sol, a second level hospital with almost 300 beds in the South of Spain. The participants were workers in the following hospital units: Emergencies, Medical Area (Internal Medicine, Chest Diseases), Surgical Area (General Surgery and Anaesthesia) of any professional category. A study was made of the proportion of healthcare workers in our hospital with positive serology for the new influenza A (H1N1)2009 virus, as determined by the haemagglutination inhibition technique (≥1/40). The subjects completed a health status questionnaire, and provided a blood sample for serology testing.ResultsA total of 239 workers participated, of whom 25.1% had positive serology. The hospital area in which most individuals had positive serology was the Emergency Department (36.6%), while the professional category in which most individuals with a positive serology worked was that of the orderlies (41.7%).ConclusionAround 25% of healthcare workers in our hospital had positive serology before the peak of the pandemic, none of them had received vaccine for Influenza A (H1N1) 2009 or had been diagnosed of influenza previously.

Evaluation of Immune Status to Measles in Vaccinated Population in Tehran, by Enzyme-linked Immunosorbent Assay and the Hemagglutination Inhibition Techniques (1386-1387)

Background and Aims: Measles remains one of the leading causes of childhood morbidity and mortality in developing countries and is still a major public health concern in developed countries. Although live attenuated vaccine is used throughout the world, out breaks of disease still occur in many countries including Iran. Methods: The present study was performed to evaluate the immune status against measles after the mass campaign vaccination in 2003. Results: In this study, Approximately 172 sera were analysed by ELISA and HI tests. The results indicated, 162 were positive (94.2%) and 10 were negative (5.8%) by HI test and 165 were positive (95.5%) and 7 were negative (4.1%) by the ELISA test. Conclusion: Understanding measles outbreaks that occur after the initiation of measles elimination efforts will be critical in refining the strategies for measles elimination.

Polyoma Viruses May Cause Chronic Cystitis and Respond to Intravesical Cidofovir

These activities are important for preparation of epidemics and pandemics. In the past decade, several outbreaks of influenza B have been reported in this country. Thus, the aims of this study are to evaluate the incidence and to identify the circulating viral strain of influenza type B in Malaysia. Methods: All respiratory specimens received from several sentinel sites from patients presenting with influenza-like illness (ILI) were included in this study. The virus was detected by culture method using Madin Darby Canine Kidney (MDCK) cells with combination of Immunofluorescence (IF) and haemagglutination inhibition (HAI) techniques. Results: From 2002 to 2006 the National Influenza Centre, IMR received a total of 5,463 specimens from patients presenting with ILI. Of these, 220 (4.0%) were found to be positive for Influenza B virus and further analysis showed that there were four major strains circulating in Malaysia during the five years study period. The predominant strain in 2002 was B/Hong Kong/330/2001-like virus, B/Sichuan/379/99-like virus in 2003, B/Shanghai/361/2002like virus in 2004, B/Hong Kong/330/2001-like virus in 2005 and B/Malaysia/2506/2004-like virus in 2006. Conclusion: The surveillance activities are not only important as an early warning for outbreak preparedness but also important in detecting new strains that can be used in the annual vaccine formulation.

Evaluation of immune status to measles in vaccinated population in Tehran, using enzyme-linked immunosorbent assay and the hemagglutination inhibition techniques

Evaluation of immune status to measles in vaccinated population in Tehran, using enzyme-linked immunosorbent assay and the hemagglutination inhibition techniques

Development of passive haemagglutination (PHA) and haemagglutination inhibition (HAI) technique for potency estimation of Cobra Antisnake Venom Serum (ASVS)

Antibodies against snake venom or antivenom potency are assayed quantitatively by in-vivo neutralization test in mice, which requires large number of laboratory animals. In potency assays of biological substances such as antivenoms, it is highly desirable to avoid suffering and death of animals by substituting in-vivo method with in-vitro methods, provided such methods measure life-saving capability with precision similar to that of in-vivo method. The in-vitro tests determine the neutralizing power of antivenom by permitting the evaluation of a particular biological activity of the venom and its neutralization after mixing the venom with the antivenom [Theakston RDG, Reid HA. Development of simple standard assay procedures for the characterization of snake venom. Bull WHO 1983;61:949–956; Gutierrez JM, Rojas G, Lomonte B, Gene JA, Chaves F, Alvarado J, et al. Standardizing of assays for testing the neutralizing ability of antivenoms. Toxicon 1990;28:1127–1129; Theakston R.D.G. Comments on letter of Gutierrez et al. on standardization of assays for testing the neutralizing ability of antivenoms. Toxicon 1990;28:1131–1132; Harvey AL, Barfaraz A, Thomson E, Faiz A, Preston S, Harris JB. Screening of snake venom for neurotoxic and myotoxic effects using simple in-vitro preparation from rodents and chicks. Toxicon 1994;32:257–265; World Health Organization Progress in characterization of venom and standardization of anti-venoms. Geneva: WHO offset publication; 1981. p. 58.]. Hence, the ideal requirements for an assay in detecting venom and venom antibody include high level of sensitivity, specificity (ability to differentiate between venom and venom antibody produced by closely related species of snakes), reproducibility and simplicity. A new in-vitro procedure for quantitative analysis of potency of ASVS by passive haemagglutination (PHA) and haemagglutination inhibition (HAI) has been explored. The methods described are simple, rapid, economical, reproducible and useful in replacing the more expensive in-vivo neutralization assays. Moreover, it also eliminates the use of laboratory animals.

Isolamento e caracterização biológica da amostra JAP99 do vírus da doença de Newcastle isolada de patos domésticos (Neta sp) no Rio de Janeiro

O vírus da doença de Newcastle (VDN) é o agente etiológico de uma das doenças mais importantes da avicultura e tem sido identificado na maioria das espécies aviárias, silvestres e domésticas. Neste trabalho, obteve-se o isolamento em ovos embrionados da amostra denominada JAP99 do VDN, a partir de fezes de patos coletadas no Município de Japeri, RJ. A amostra foi identificada pela técnica da inibição da hemaglutinação (HI) e a caracterização biológica da patogenicidade do novo isolado foi realizada no Laboratório Regional Animal, MAPA, Campinas, SP (LARA-Campinas). Pela inoculação intracerebral em pintos de um dia (IPIC), o índice foi 1,4. Na inoculação intravenosa em aves de seis semanas (IPIV), o índice encontrado foi 0,0 (zero) e o tempo médio de morte embrionária (TMME) foi de 62 horas. Estes resultados indicaram que o isolado JAP99 é mesogênico para galinhas comerciais, oferecendo risco para a avicultura industrial.

The status of rubella immunity among pregnant women in Kuwait: screening in childbearing age should be reintroduced

The objective of this study was to investigate the immunity against rubella in the obstetric population in Kuwait by testing 600 pregnant women at a prenatal clinic, using the haemagglutination inhibition technique. In addition, a comparison was made between this study and one done in 1978 at the same clinic; its relation to the vaccination programme is also discussed. 7.7% of the population under study were non-immune. Statistically significant effect was demonstrated for maternal age but not for parity and nationality. Though it has been almost 20 years since an intense rubella vaccination programme was implemented, the percentage of non-immune pregnant women has not decreased. In Kuwait, termination of pregnancy for congenital rubella syndrome is prohibited. As a result, it is recommended that women be screened and vaccinated at the time of marriage.