Nanoemulsion of eucalyptus oil and its larvicidal activity against Culex quinquefasciatus.

Filariasis is a mosquito-borne disease that causes lymphedema and the main vector is Culex quinquefasciatus. A simple measure was taken to eradicate the vector using nanoemulsion. Eucalyptus oil nanoemulsion was formulated in various ratios comprising of eucalyptus oil, tween 80 and water by ultrasonication. The stability of nanoemulsion was observed over a period of time and 1:2 ratios of eucalyptus oil (6%) and surfactant (12%) was found to be stable. The formulated eucalyptus oil nanoemulsion was characterized by transmission electron microscopy and dynamic light scattering. The nanoemulsion droplets were found to have a Z-average diameter of 9.4 nm and were spherical in shape. The larvicidal activity of eucalyptus oil nanoemulsion and bulk emulsion was tested and compared. Our nanoemulsion showed higher activity when compared to bulk emulsion. The histopathology of larvae-treated and untreated nanoemulsion was analyzed. Furthermore, biochemical assays were carried out to examine the effect of nanoemulsion on biochemical characteristics of larvae. The treated larval homogenate showed decrease in total protein content and a significant reduction in the levels of acetylcholinesterase. The levels of acid and alkaline phosphatase also showed reduction as compared to control larval homogenate.

Chronic liver disease. A case control study of the effect of previous blood transfusion.

A means of assessing hepatitis NANB virus infection, via blood transfusion, as a cause of chronic liver disease was investigated in a hospital in each of two cities in England. Patients with chronic liver disease were matched for age and sex with other patients in the same hospital and histories taken included details of previous operations and blood transfusions; if these were within ten years of the study enquiries were made of hospital records officers. All positive histories were found correct, but about one third of previous transfusions had been omitted by both case and control patients. Sixty-seven male and 35 female patients with chronic liver disease and their controls were included in analyses. The only clear difference which emerged related to residence for more than a year in the Middle or Far East by male case- (40%) or control- (21%) patients (P less than 0.05). The exclusion of patients with this history left only 34 pairs in which five (15%) of the case patients and one (3%) of the control patients had a transfusion history: this difference was not statistically significant. Although the study results have shown no clear evidence of blood transfusion as a major cause of chronic liver disease in Britain, the study method, with sufficient numbers to allow analyses of newly diagnosed patients with confirmed transfusion histories, could be used to provide an ongoing assessment of the risk.

Chlamydial serology in fertile and infertile women.

Species-specific circulating antibodies to Chlamydia trachomatis were found in 75% of 48 infertile women with damaged fallopian tubes, 47.5% of 40 parous women seeking sterilisation, 46% of 63 women seeking termination of pregnancy, 31% of 75 infertile women with normal fallopian tubes, and 24% of 72 women using barrier contraception. High titres of antibody (greater than or equal to 1/1024) were found in 46%, 15%, 16%, 8%, and 7% of these groups, respectively, and were common in those women with a history of pelvic inflammatory disease or use of an intrauterine device. Thus, although the presence of antibody to C trachomatis was correlated with tubal damage, it was not diagnostic of tubal disease, since a substantial number of pregnant or potentially fertile women also had serological evidence of chlamydial infection. However, the results show that high titres of chlamydial antibodies in infertile women indicate the need for early laparoscopy to assess tubal status.

Hepatitis B in seven hospitals for the mentally handicapped.

Patients in seven hospitals for the mentally handicapped were screened for markers of hepatitis B infection. Of 2239 patients, 123 (5.5 per cent) were carriers of hepatitis B surface antigen (HBsAg) and a third of these were 'infectious' (negative for antibody to hepatitis B e antigen). Patients with Down's syndrome (DS) were 18 times more likely to be 'infectious' carriers than those without, and male patients were six times more likely to be 'infectious' carriers than female patients. There was a wide difference in carrier rate among the various hospitals. In the hospital with the highest carrier rate (12.5 per cent), 60 per cent of male patients with DS were carriers of HBsAg and of these two-thirds were 'infectious'. The carrier rate decreased with age, but the proportion of carriers who were hepatitis B e antigen positive was unaffected by age.

Infant-initiated weaning from the breast in the first year.

Mothers of 50 healthy breast-fed infants for whom weaning had been completed by the first birthday were administered a maternal feeding and weaning questionnaire developed by the authors. A major purpose of the questionnaire was to investigate the phenomenon of infant-initiated weaning, which is commonly, but somewhat misleadingly referred to as 'self-weaning'. 46% of the infants were reported by their mothers to have initiated weaning. The onset of this behavior occurred most frequently at 5 and 9 months of age. Most mothers attributed it to their infants' increased exploratory and nutritional desires and a concomitant reduced interest in breast-feeding. It is suggested, that rather than being weaning behavior per se, this behavior (at least that which occurs between approximately 5 and 9 months of age) may actually be a common correlate of the cognitive and physical discontinuities or 'spurts' in development which are known to occur during this interval, but that it can, and often does indirectly lead to a relatively easy mutual weaning from the breast if met with appropriate and timely maternal intervention.

Causes of pneumonia presenting to a district general hospital.

The incidence of bacterial, viral, mycoplasma, and rickettsial infections has been assessed prospectively in 210 adult patients with pneumonia who presented to a district hospital over a six-year period. One hundred and thirteen infective agents were detected in 103 patients. The agent most frequently detected was Mycoplasma pneumoniae which accounted for 30 infections. A bacterial pathogen was found in 43 patients. Streptococcus pneumoniae was the most common of these (24 patients); Staphylococcus aureus (eight), Haemophilus influenzae (four), Klebsiella spp (three), and Legionella pneumophila (three) were all less common. Chlamydial or rickettsial infections (Psittacosis or Q fever) were detected in nine patients. Viral infections were found in 31 patients (22 influenza A, four influenza B, two parainfluenza, and three respiratory syncytial virus). There were 10 patients in whom more than one pathogen was identified. In 107 patients no pathogens could be identified. Seventy-five per cent of these patients had either received antibiotics before entering hospital, or were unable to produce any sputum for culture. The incidence of bacterial pneumonia has probably therefore been underestimated. Nevertheless this survey does emphasise the importance of M pneumoniae as a pathogen in patients with pneumonia presenting to hospital.

Incidence of Legionnaires' disease in a district general hospital.

In order to assess the incidence of Legionnaires' disease in a district general hospital, 90 consecutive patients with pneumonia seen over a 3-year period were investigated. Only 2 patients were found to have Legionnaires' disease, indicating that it is not a frequent cause of pneumonia in the Bristol area.

An outbreak of gastroenteritis in young children caused by adenoviruses.

During October and November, 1978, gastroenteritis developed in 17 of 24 young children aged between eight months and two years from an R.A.F. station in the U.K. The illness, in which diarrhoea was always the predominant symptom, had an incubation period of eight to ten days and lasted about a week. It seemed to be transmitted from child to child, and in all but one instance parents and older siblings remained well. Stool specimens from 14 of the affected children were examined bacteriologically and virologically, and a highly significant association was found between the presence of adenovirus particles in stools, identified by electron microscopy, and the acute stage of the illness. This evidence suggests that an adenovirus was the cause of this outbreak of gastroenteritis.

A double-blind cross-over study of the effect of doxycycline on mycoplasma infection and infertility.

Forty-two couples in an infertility clinic were examined for genital infection with Mycoplasma hominis or Ureaplasma urealyticum (T strains). In 21 couples one or other partner was found to be infected; no chlamydiae, trichomonads, or gonococci were isolated from any of these couples. All patients were then included in a double-blind crossover doxycycline/placebo study lasting 8 months. Pregnancy was achieved in one of the 21 couples who were free of infection. Of the 21 couples who were infected, one achieved a pregnancy while still infected, and 19 lost their infection on doxycycline, of whom four achieved a pregnancy. These four pregnancies all occurred among the 10 couples who received doxycycline first. One further pregnancy occurred after the trial was over. Since 5 of the 7 pregnancies occurred in the first 4 months of the trial, they were probably due to the psychological effect of treatment rather than the effect of the drug on infection.

The human enteric coronaviruses.

A coronarirus was seen in the faeces from 15 (4.2%) of 355 adults with diarrhoea and from 5 (5.2%) of 96 adults without diarrhoea. Similar particles were seen in the faeces from 5 (2.2%) of 227 children aged 1--14 years with gastroenteritis, but in none of those from 230 infants under one year of age with gastroenteritis. There was no evidence that the coronavirus was responsible for any of 34 outbreaks of gastroenteritis, although it possibly caused diarrhoea in patients admitted to a psycho-geriatric unit. Excretion of the virus often continued for many months. One strain was propagated in human embryo kidney monolayers and human embryo intestinal organ cultures, although serial passage could not be accomplished.

Evaluation of a simplified sucrose gradient method for the detection of rubella-specific IgM in routine diagnostic practice.

Rubella-specific IgM was measured in a single fraction of serum from a sucrose density gradient. Haemagglutination inhibition (HAI) tests were performed on paired aliquots of the fraction untreated and after treatment with 2- mercaptoethanol, dilutions of the aliquots being incubated over night with rubella antigen before the addition of red cells. Of 822 sera tested, specific IgM was found in 249, but not in 492. When first tested, the remaining 81 sera gave unsatisfactory results because of contamination of the IgM fraction with IgG (6.0%), probable aggregation of IgG (3.5%), or the persistence of chick red cell agglutinins (0.4%). Tests were performed on 134 patients with rubella confirmed by a rise of HAI antibodies. Rubella-specific IgM was found at a titre of more than eight in the sera taken from 62 of 64 patients between 10 and 29 days after the onset of the rash but in only one of the sera taken between 80 and 119 days, and in none taken later. However, specific IgM was still to be found at lower titre in the sera of 13 patients collected between 80 and 162 days after the onset of the illness. In routine diagnostic tests over three years on the serum from 479 patients with suspected acquired rubella, specific IgM was found at a titre of more than eight in 51 patients and in only 10 instances (2.1%) did a lower level pose a problem in interpretation.

A comparison of influenza and respiratory syncytial virus infections among infants admitted to hospital with acute respiratory infections.

Among 741 children under 5 years admitted to hospital with respiratory infections during two winters, infection with influenza A virus was diagnosed in 70 (9%), with influenza B virus in 8 (1%), and with respiratory syncytial virus (RSV) in 259 (35%). Both influenza virus and RSV infections were diagnosed most frequently in children under the age of one year, and diagnosed more frequently in males than females. Influenza illnesses were more severe in boys than girls. Both infections occurred more often, but were not more severe, in children from a conurbation than in those from 'rural' areas. Convulsions were the cause of 36% of admissions with influenza A infections, but were rare in RSV infections. Bronchiolitis was the reason for 39% of admissions with RSV infections, but was rare in influenza infections. It is suggested that infants admitted to hospital are a good source of influenza virus strains for monitoring antigenic variation.

Comparison of human fecal and serum parvo-like viruses.

Parvovirus-like particles found in the sera of two blood donors had the size and appearance on electron microscopy of a virus (B19) found in the serum of a blood donor by Cossart et al. (1975), and those of a virus found in the feces of a normal subject. Antibody to these viruses was detected by immune electron microscopy and immunoelectro-osmophoresis in the sera of 50 children aged 10 to 15 years. Of these, 36% had antibody to the fecal virus, 36% had antibody to B19, and 54% had antibody to the two other serum viruses. The results of these tests suggest that serologically the three serum viruses were similar to one another, but that the fecal virus was distinct. The two blood donors had nonspecific symptoms at the time of viremia. Both donors had developed immunoglobulin M antibody to the virus when tested 3.5 and 4.5 weeks later, but no viruses were detected in the feces or urine.