Two randomized controlled trials of virucidal nasal tissues in the prevention of natural upper respiratory infections

Two six-month randomized, controlled double-blind trials of the efficacy of virucidal nasal tissues in the prevention of natural colds were conducted in Charlottesville, Virginia, between 1983 and 1986. Tissues impregnated with malic and citric acids and sodium lauryl sulfate were used in both trials. Placebo tissues contained saccharin in the first trial and a mixture including succinic acid in the second. A total of 186 families were evaluable after completion of trial I, and 98 families were evaluable in trial II. The antiviral tissues were associated with 14 and 5% relative reductions in the overall rate of colds in the first and second trials, respectively. In the first study, this appeared to be due to an appropriate fall in secondary illnesses with a relative reduction in the ratio of secondary to primary illnesses of 32%. In trial II, however, the small and statistically insignificant reduction was primarily due to a drop in the rate of primary illness (which cannot be attributed to tissue efficacy), and the ratio of secondary to primary illness was actually 5% higher in the group with active tissues than in the placebo group. We conclude that when rigorously used in a study protocol, virucidal tissues may offer a modest reduction of secondary colds in the home, but for reasons currently unknown, do not have a major effect on the overall rate of colds.

Diagnosis and patterns of incidence of influenza, influenza-like illness and the common cold in general practice

The incidence of influenza, influenza-like illness and the common cold during the influenza epidemics of 1972 and 1976 as reported to the weekly returns service of the Royal College of General Practitioners was examined by three regional areas and by age group. The results of a postal questionnaire concerned with diagnostic criteria used by participating doctors were also analysed. These two analyses were used to explore the validity of these diagnostic terms as reported in the weekly returns service.The two influenza epidemics peaked at about the same time throughout the country and in all age groups simultaneously, although the severity of the epidemic seemed to wane from south to north in 1976. The reported incidence of influenza-like illness and of the common cold was less in the central region than in the north and south during both the two epidemic years. Influenza incidence was maximal in age groups 15-44 and 45-64 years, whereas the reported incidence of influenza-like illness and the common cold was maximal in pre-school children.Additionally, influenza-like illness and the common cold appeared to a fairly uniform extent every winter whereas influenza was truly epidemic.From the questionnaire to general practitioners, the symptoms of rigors, malaise and myalgia and the recognition of an epidemic were the important criteria which differentiated influenza from influenza-like illness.We conclude that in general practice the distinction between influenza and influenza-like illness is reliably made and has validity in the clinical context and meaning of these diagnostic terms.

[The significance of social and familial factors]

In the epidemiological group-diagnostic investigations of children taking place in the areas of Rhein/Main, Freiburg and Starnberg in 1982-1986, we registered supplementary characteristic of the familiar and social environments of the children by questionnaires in the years 1982/1983. From the results of the statistical evaluations we see that the health of the examined children responds equally to the social and familiar surroundings, such as housing space, indoor pollution, and social stimulants to the air quality or the meteorological and geographical characteristics of the different regions.

Video display terminal use and reported health symptoms among Massachusetts clerical workers

Few well-controlled studies have assessed the extent and magnitude of adverse health conditions reported by video display terminal (VDT) operators. To evaluate the association between typical, daily VDT use and the prevalence of adverse conditions related to vision, musculoskeletal conditions, headaches, and colds or sore throats, we conducted a cross-sectional, epidemiologic study of 1,545 Massachusetts clerical workers. The study results indicated an increased prevalence of adverse conditions pertaining to vision, musculoskeletal discomfort, and headaches among clerical workers who used VDTs. The magnitude of the increased prevalence was dose dependent. The effects related to musculoskeletal discomfort and headaches were higher among VDT workers in computer and data processing services, public utilities, and the Commonwealth of Massachusetts than among workers in banking, communications, and hospitals. These latter effects, however, may have been due to random variation.

Prospective epidemiological study of common colds and secretory otitis media

To evaluate how often a common cold induces secretory otitis media (SOM) two groups of young children were studied. One comprised 373 children aged 9 months to 7 years who were being minded in institutions. The other group consisted of 210 children not minded in day institutions or private day care. This latter group was subdivided into children minded at home or in private day care attended by not more than 2 children (117 children), and the remainder (93 children). Common colds were defined as nasal discharge, and tympanometry was carried out 6 times at 2-week intervals. Among the 1-year-olds common colds induced SOM in 83% of those minded in institutions and in 56% of those minded at home. At the age of 5 years this applied to 20% of both groups.

Physical and emotional responses of expectant fathers throughout pregnancy and the early postpartum period

A comparative, repeated measures survey design was used to monitor the physical and emotional health of 81 expectant fathers and 66 non-expectant men over the course of a year at monthly intervals. A total of 877 monthly data collection episodes were completed. Compared to non-expectant men, expectant fathers were found to experience relatively similar patterns of both physical and emotional symptoms throughout the three trimesters of pregnancy. However, expectant fathers' health was found to differ significantly from that of non-expectant men during the immediate postpartum period with a greater incidence of emotional discomforts as well as total number of symptoms, their duration and perceived seriousness. Included are recommendations for anticipatory health counseling to promote health in expectant fathers.

Eosinophils, smoking, and lung function. An epidemiologic survey among 912 working men

The relationship of eosinophilia with smoking habits and with baseline lung function measurements has been studied in a working population of 912 men in the Paris area. Absolute numbers of eosinophils were related significantly to a history of asthma and eczema in childhood as well as to current tobacco consumption, whereas the percentage of eosinophils was related only to the occurrence of asthma and eczema. Forced expiratory volume in one second adjusted for smoking was significantly related to asthma, the presence of a common cold on the day of examination among those with a history of wheezing, and the percentage of eosinophils. The association between FEV and eosinophils was restricted to never smokers. Among never smokers without a history of asthma, eczema, wheezing, or a common cold on the day of examination, eosinophil percentages and counts were significantly associated with the level of FEV; eosinophil percentages explained 4.4% of the variance of FEV. These results suggest that eosinophilia might be a risk factor for chronic air-flow limitation among adult nonsmokers.

Epidemiology of common cold

The epidemiology of common cold and the role of some predisposing factors were studied by examining 2065 healthy children, aged 2.5-6 years. The examination included a questionnaire, completed by the parents, a general physical examination, a clinical E.N.T.-examination and various technical investigations. The mean annual incidence of common cold was 2.43 (as was reported by the parents) and 5 when taking into consideration the time span between the last episode of common cold and the date of examination. Mucoid and purulent rhinitis were less frequently found in older children. A positive history of upper respiratory tract infections in the parents showed to be the most important risk factor for the occurrence of infectious rhinitis in the children. The higher the weight of the child, the lower the incidence of common cold and the fewer pathological rhinoscopical findings. Children with a head circumference below the 2.5 percentile had the highest incidence of infectious rhinitis. Humid housing conditions showed to be connected with a higher incidence of infectious rhinitis. Children of parents with a higher profession had more rhinitis than children of labourers. Smoking habits of the parents had only little effect on the rhinological status of children.

Epidemiology of community-acquired respiratory tract infections in adults. Incidence, etiology, and impact

Upper respiratory tract infections are the most common types of infectious diseases among adults. It is estimated that each adult in the United States experiences two to four respiratory infections annually. The morbidity of these infections is measured by an estimated 75 million physician visits per year, almost 150 million days lost from work, and more than $10 billion in costs for medical care. Serotypes of the rhinoviruses account for 20 to 30 percent of episodes of the common cold. However, the specific causes of most upper respiratory infections are undefined. Pneumonia remains an important cause of morbidity and mortality for nonhospitalized adults despite the widespread use of effective antimicrobial agents. There are no accurate figures on the number of episodes of pneumonia that occur each year in ambulatory patients. In younger adults, the atypical pneumonia syndrome is the most common clinical presentation; Mycoplasma pneumoniae is the most frequently identified causative agent. Other less common agents include Legionella pneumophila, influenza viruses, adenoviruses, and Chlamydia. More than half a million adults are hospitalized each year with pneumonia. Persons older than 65 years of age have the highest rate of pneumonia admissions, 11.5 per 1,000 population. Pneumonia ranks as the sixth leading cause of death in the United States. The pathogens responsible for community-acquired pneumonias are changing. Forty years ago, Streptococcus pneumoniae accounted for the majority of infections. Today, a broad array of community-acquired pathogens have been implicated as etiologic agents including Legionella species, gram-negative bacilli, Hemophilus influenzae, Staphylococcus aureus and nonbacterial pathogens. Given the diversity of pathogenic agents, it has become imperative for clinicians to establish a specific etiologic diagnosis before initiating therapy or to consider the diagnostic possibilities and treat with antimicrobial agents that are effective against the most likely pathogens.

The Jeremiah Metzger lecture. Climatology and the common cold

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Statistical procedures for estimating the community probability of illness in family studies: rhinovirus and influenza

A statistical method is presented for determining acquisition rates of illness from community sources of infection and for distinguishing among viruses which are associated with different epidemic seasons. The new method consists of a computationally simple procedure for estimating the community transmission parameter and the standard error of the estimator. This method, as well as a previously developed maximum likelihood procedure, is applied to illness data as a means for distinguishing among broad patterns of illness acquisition. The periods evaluated are the rhinovirus, influenza A and influenza B seasons in Tecumseh, Michigan, for the years 1976-1980. Tecumseh households are stratified into exposure groups depending on age-group composition. Estimates are found for the risk differences of illness acquired from the community for households with different age-group distributions. Analysis of the Tecumseh data reveals that members of households with children are more apt than members of households without children to acquire illness associated with rhinovirus, influenza A and influenza B from the community. Members of households with just preschool children (and adults) are more apt than members of households with just school children (and adults) to acquire illness associated with rhinovirus and influenza B from the community. In contrast, members of households with just preschool children (and adults) are just as likely as members of households with just school children (and adults) to acquire illnesses associated with influenza A from the community.

Do parkinsonian patients have a greater resistance to the common cold?

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Diarrhea and school toilet hygiene in Cali, Colombia

In a 4-week period in early 1976 in a poor, working class area of Cali, Colombia, the prevalences of diarrhea, vomiting, common cold, and head lice in schoolchildren were measured in relation to classroom size and to the condition of the school toilets. The study found that unhygienic toilet conditions were related to diarrhea, and it was estimated that if all schools could reach the modest level of hygiene of the two schools with the relatively best facilities, diarrhea would be reduced by 44% and vomiting by 34%. Toilet hygiene was found to be unrelated to colds or head lice, which have similar social class distributions to diarrhea and vomiting. Crowding was found to be related to a small percentage of the prevalences of vomiting, head lice and colds.

Effects of adenoidectomy: a controlled two-year follow-up

A prospective controlled study was made on the effect of adenoidectomy performed on 105 children. For various reasons, mainly severe long-standing nasal obstruction, 29 children were omitted from the study. The remaining 76 children were randomly divided into two groups, one adenoidectomy, and one control. Both groups were slightly reduced in number due to drop out. Thus 36 adenoidectomized children were followed during one year and 35 children during two years. The corresponding numbers for the children in the control group were 37 and 33. The incidence of common cold, purulent and serous otitis media and moderate nasal obstruction was compared in the two groups. A considerable reduction in the incidence of these variables was observed in both groups. The occurrence of moderate nasal obstruction was reduced more among the operated than among the unoperated children. The difference was only slightly significant during the first and not at all during the second year. Regarding the other variables, the differences were not significant, implying that adenoidectomy seems to have no effect on the incidence of common cold, serous and purulent otitis media.

Therapeutic effect of vitamin C. A co-twin control study

Three different dosages of vitamin C, dependent on body weight, were administered to 44 school-aged monozygotic twins for five months using a double-blind, co-twin control study design. The mothers recorded daily observations of cold symptoms, and multiple biochemical, anthropometric, and psychological measurements were made at the beginning and end of the study. Paired comparisons showed no significant overall treatment effect on cold symptoms, but the response was not uniform in all sub-groups. Treated girls in the youngest two groups had significantly shorter and less severe illness episodes, and an effect on severity was also observed in the youngest group of boys. The seven treated twins in the latter group also grew an average of 1.3 cm more than their untreated co-twins during the five-minth period of the study.

Measurements of the prevalence of viral infections

Viral diseases exert their major impact through morbidity, impairment of personal health, loss of time at work and school, and cost of medical care. Relatively few of the known viruses cause a significant number of deaths; influenza, childhood viral pneumonia, and hepatitis are the only viral diseases causing more than 1,000 deaths per year. Data based on the National Health Interview Survey of the National Center for Health Statistics show that the common cold annually causes 35.6 acute illnesses per 100 persons. The data reported by the National Therapeutic Disease Index (on the basis of visits by patients to a sample of 1,500 private physicians) show that influenza and other acute respiratory conditions account for about one-third of all visits to physicians. Nearly all viruses first infect humans in infancy and childhood, with a relatively low fatality rate but with frequent episodes of illness.

Studies of respiratory morbidity in rubber workers. Part III. Respiratory morbidity in processing workers

Respiratory questionnaires and pulmonary function tests were administered to sixty-five men exposed to dust in the processing are from three rubber tire manufacturing plants. Similar tests were done on 189 "control" workers. Compared with the controls, the processing workers had a higher prevalence of chronic productive cough. Overall, the processing group showed a decrease in the ratio of FEV to FVC. The processing workers with more than ten years of exposure showed a significant decrease in the ratio of FEV1.0/FVC, the FEV1.0, the residual FEV1.0, and the flow rates at 50% and 25% of the forced vital capacity. None of the pulmonary function effects could be solely explained on the basis of smoking, age, ethnic, or socioeconomic factors: all were related to the length of exposure. Based on these results we conclude that exposure in the processing area produces pulmonary disease.

Respiratory virus infections in travellers

Respiratory viruses affect travellers, but the main significance of this is probably that it is in this way that the viruses reach new hosts and thus survive as infectious agents.

The perception of the common cold, and other ailments and discomforts, as related to age

Perception of the common cold and other discomforts was studied as a function fo age among 456 normals ranging in age from 18 to 82. Respondents completed a questionnaire which deal with the frequency and duration of their colds, their symptoms and treatments-and, finally, with the perceived severity of various discomforts. Though older Rs were found to suffer more than younger with body aches, the former had less difficulty with a variety of other physical and psychological symptoms-and also contracted relatively few colds. Older Rs treated their colds less often with Contac and Dristan, but more often by staying home and/or calling their doctor. As compared with younger Rs, older respondents perceived intestinal flu to be relatively less serious-but earache, sprained toe, indigestion, having a tooth filled, stiff neck, and hangover to be relatively more serious.

Greater frequency of viral respiratory infections in asthmatic children as compared with their nonasthmatic siblings

A longitudinal clincal and microbiologic surveillance was conducted from October to May, 1971-72, on 16 children with infectious asthma and 15 of their nonasthmatic siblings. Asthmatic children experienced a significantly greater frequency of viral respiratory infections than did nonasthmatic ones (5.1 vs. 3.8 per subject). This increased incidence appeared to be largely the result of a greater number of rhinovirus infections. While respiratory infections of identical etiology that occurred concurrently in an asthmatic and his sibling were equivalent in severity, illnesses were longer (but not significantly so) in asthmatic children.

Common colds in Antarctica

Recent studies have established that the occurrence of common cold epidemics amongst men in Antarctica shows a pattern similar to that seen in other isolated communities such as Tristan da Cunha (Cameron & Moore, 1968; Shibli, Gooch, Lewis & Tyrrell, 1971). Colds occur during relief periods when ships and aircraft call, and disappear during the months of winter isolation, but no statistical analysis of the incidence of such colds is available.

An outbreak of common colds at an Antarctic base after seventeen weeks of complete isolation

Six of 12 men wintering at an isolated Antarctic base sequentially developed symptoms and signs of a common cold after 17 weeks of complete isolation. Examination of specimens taken from the men in relation to the outbreak has not revealed a causative agent.