Hay Fever is a disease which on account of its peculiar interest has attracted the attention of the medical world ever since it was first accurately described by Bostock of London in 1819. To what extent the disease occurred before his time is difficult to determine; but from the fact that his observations were at once confirmed by a number of contemporary medical men it is probable that at the time of his writing it was not very uncommon. We have no exact knowledge of the existence of the disease in England prior to the nineteenth century, and indeed many authors hold that the chief etiological factors were not present in earlier times. It is my purpose in this paper to discuss the researches recently carried out by Prof. Dunbar at the State Institute of Public Health in Hamburg, which have very considerably increased our knowledge of the interesting malady, and have also narrowed the field for its future investigation.

The outbreak of coronavirus disease-2019 (COVID-19) impacts public health dramatically around the world. The demographic characteristics, exposure history, dates of illness onset and dates of confirmed diagnosis were collected from the data of 24 family clusters from Beijing. The characteristics of the cases and the estimated key epidemiologic time-to-event distributions were described. The basic reproductive number (R0) was calculated. Among 89 confirmed COVID-19 patients from 24 family clusters, the median age was 38.0 years and 43.8% were male. The median of incubation period was 5.08 days (95% confidence interval (CI) 4.17–6.21). The median of serial interval was 6.00 days (95% CI 5.00–7.00). The basic reproductive number (R0) was 2.06 (95% CI 2.02–2.08). The median of onset-to-care-seeking days and the median of onset-to-hospital admission days were significantly reduced after 23 January 2020, which implied the enhanced public health awareness among families. With epidemic containment measures in place, the results can inform health authorities about possible extent of epidemic transmission within families. Furthermore, following initiation of interventions, public health measures are not only important for curbing the epidemic spread at the community level but also improve health seeking behaviour at the individual level.

Of all British colonies New Zealand is the one that most closely resembles Great Britain in size, in situation, and in climate. And the inhabitants of the two countries are of practically the same race. The vital statistics of New Zealand are therefore eminently suitable for comparison with those of Great Britain. In the present paper comparison has been restricted to the birth-rates and death-rates, and in this limited survey several points of interest present themselves.

The Bacillus capsulatus-mucosus group may be said to have originated with the discovery of the pneumobacillus by Friedländer in 1883. This organism was isloated from the lung in a case of croupous pneumonia, and it is interesting to note, as can be ascertained from a study of the literature, that the discovery appears to have been of an accidental nature, and, as was pointed out by Weicheselbaum, that Friedläder had really confused it with the pneumococcus. Subsequently, numerous other bacilli, which showed such marked similarity to the pneumobacillus in morphological, cultural and biological characteristics as to render differentiation among them a matter of extreme difficulty, were isolated by various workers from widely different sources. In a paper published in 1896 Fricke furnishes a list of the representatives of this group of organisms which had up to that time been found. Many of these were subsequently used as type strains by later workers and some are still available and frequently employed.

1. Some simple “field” work on the disinfestation of empty, bug-ridden houses by means of liquid insecticides and a simple experiment with an occupied house are described.

2. A method of obtaining an estimate of the number of bugs killed by the application of liquid insecticides is given as well as some information about the number of bugs found in houses. More than 2000 dead bugs were found in one small house.

3. The aliphatic thiocyanate, β-butoxy-β′-thiocyanodiethylether, was tried in four different oil carriers and gave good results as a 3% solution (6% Lethane). A pyrethrum preparation in a heavy oil carrier also showed promise. A mixture of the two toxic substances was tried and found to be effective.

4. The methods of applying the insecticides are described. Good results were obtained with an ordinary hand sprayer of the horticultural type, giving a continuous spray. The premises were not sealed, but on a few occasions wood fittings were eased or removed.

Severe infections and psychiatric disorders have a large impact on both society and the individual. Studies investigating these conditions and the links between them are therefore important. Most past studies have focused on binary phenotypes of particular infections or overall infection, thereby losing some information regarding susceptibility to infection as reflected in the number of specific infection types, or sites, which we term infection load. In this study we found that infection load was associated with increased risk for attention-deficit/hyperactivity disorder, autism spectrum disorder, bipolar disorder, depression, schizophrenia and overall psychiatric diagnosis. We obtained a modest but significant heritability for infection load (h2 = 0.0221), and a high degree of genetic correlation between it and overall psychiatric diagnosis (rg = 0.4298). We also found evidence supporting a genetic causality for overall infection on overall psychiatric diagnosis. Our genome-wide association study for infection load identified 138 suggestive associations. Our study provides further evidence for genetic links between susceptibility to infection and psychiatric disorders, and suggests that a higher infection load may have a cumulative association with psychiatric disorders, beyond what has been described for individual infections.

Individuals developing an HIV seroconversion illness may experience rapid disease progression. Information on seroconversion illness is rarely collected in most cohort studies; thus the aim of this study was to assess the value of the HIV test interval (the time between last negative and first positive HIV tests) as a proxy for seroconversion illness. Among 8229 seroconverters, test intervals ranged from 0–5282 days, and varied by gender, risk group, age and calendar year of seroconversion. Those with intervals [les ] 31 days had an increased hazard of AIDS (RH 1·42, P = 0·07), which was reduced slightly after adjusting for baseline factors, calendar year of follow-up, treatment and the declining CD4 count, but there was no effect on survival. Thus, it appears that if information on acute seroconversion illness is not available, then analyses of progression to AIDS in seroconverter studies could use a short test interval as a proxy measure.

When a 1:5 mixture of trimethoprim (TMP) and sulphadiazine was fed to pigs intra-nasally infected with Bordetella bronchiseptica, 10 mg/kg/day was shown to be highly effective in suppressing the organism. This dose level had little effect on numbers of TMP-resistant coliforms in faeces, but oral doses of 30 mg/kg/day eventually selected a resistant population. It is suggested that the proliferation of resistant coliforms would be minimized by administration of the lowest oral dose rates of antibacterial drugs compatible with efficacy.

It was Heraclitus who said of his predecessors that they had much knowledge but no sense, and this criticism often comes to mind when workers pause in retrospect and wonder that the application of the quite adequate knowledge of a generation ago was not applied in a practical and wise manner. Perhaps it may seem that a long time elapsed after compulsory education was adopted before it was realized that a vast number of children were physically quite unfitted to benefit from the learning presented to them; and it was a still longer time before it was hesitatingly acknowledged that the art of living, the teaching of an hygienic way of life, was the most important aspect of education. For without this the benefits of the whole system are of little lasting worth or real utility. Thus it is that open-air education, born late in time, is of such paramount importance; because although ordinarily and primarily conceived for restoring delicate children to health, the main great permanent value of this work is that it teaches in a practical and pleasant manner the greatest of all arts—the art of living.

In his classical treatise on Contagions, Hieronymus Fracastorious of Verona has the following passage: “I recollect a singular contagion of the year 1514 which affected only oxen; it first showed itself in the district of Frioli, then gradually extended to northern Italy and thence reached our country. At first the ox went off its feed without any obvious cause, but if the herdsmen looked into the mouth a certain roughness and small pustules were noted on the palate and the whole oral cavity. It was necessary at once to isolate the infected beast from the rest of the herd, otherwise all became affected. Gradually the disease descended to the shoulders and thence to the feet, and almost all the beasts in which this happened recovered, but when it did not, they usually died” (Fracastorii, pp. 63–4). Probably, as in the parallel case of influenza, a careful search of earlier literature might show that foot-and-mouth disease had played its part before 1514. It is sufficient for my present purpose to establish that it has been recognised, very much in its actual clinical form for more than 400 years.

Gye and Kettle (1922), from a study of the effects of subcutaneous inoculation of silica alone, tubercle bacilli alone and tubercle bacilli with silica, arrived at the conclusion that there is, after the introduction of tubercle bacilli with silica, “a much greater local reaction than with an infection of tubercle bacilli alone and, further, that general dissemination is earlier and more active.” As a result, “a small dose of bacilli becomes a dose of considerable magnitude and, inasmuch as an important factor in determining an infectious process is the number of organisms introduced, a simple explanation is forthcoming of the effect of silica upon such tuberculous lesions as we have described.”

Hand-foot-mouth disease (HFMD) is an acute infectious disease caused by serotypes of the enterovirus (EV) family. HFMD reinfection occurs commonly in lack of cross-protection between different EV serotypes. In this study, we investigated the hazards of HFMD reinfection using Cox-proportional hazard model. Retrospective data of 95 209 HFMD cases in Wuhan during 2008–2015 was used. Kaplan–Meier survival methods and Cox-proportional hazard model were used to estimate the hazard probabilities. Of the all HFMD cases, about 2% experienced reinfection (1842/95 209). Kaplan–Meier curves revealed the reinfection risk sharply increased before 40 months from first infection. Higher hazards of reinfection were detected among those who were males, aged 3 years and below, scattered children, belonging to urban areas and first infected with coxsackievirus (CV)-A16 compared with their respective counterparts. Cox-proportional hazard model suggested that gender, age, group, living area and serotypes of first infection had significant effect on reinfection even after adjusting for potential confounding effects of other selected factors considered in the study. These results indicate that boys aged 3 years and below, especially those living in urban areas and first infected with CV-A16 are more prone to reinfection. Interventions should be imposed on these high-risk populations.

This study determined long-term health outcomes (≥10 years) of Q-fever fatigue syndrome (QFS). Long-term complaints, health-related quality of life (HRQL), health status, energy level, fatigue, post-exertional malaise, anxiety, and depression were assessed. Outcomes and determinants were studied for the total sample and compared among age subgroups: young (<40years), middle-aged (≥40–<65years), and older (≥65years) patients. 368 QFS patients were included. Participants reported a median number of 12.0 long-term complaints. Their HRQL (median EQ-5D-5L index: 0.63) and health status (median EQ-VAS: 50.0) were low, their level of fatigue was high, and many experienced post-exertional malaise complaints (98.9%). Young and middle-aged patients reported worse health outcomes compared with older patients, with both groups reporting a significantly worse health status, higher fatigue levels and anxiety, and more post-exertional malaise complaints and middle-aged patients having a lower HRQL and a higher depression risk. Multivariate regression analyses confirmed that older age is associated with better outcomes, except for the number of health complaints. QFS has thus a considerable impact on patients’ health more than 10 years after infection. Young and middle-aged patients experience more long-term health consequences compared with older patients. Tailored health care is recommended to provide optimalcare for each QFS patient.

Chickenpox (varicella) is a rare occurrence in healthcare settings in the USA, but can be transmitted to healthcare workers (HCWs) from patients with herpes zoster who, in turn, can potentially transmit it further to unimmunized, immunosuppressed, at-risk, vulnerable patients. It is uncommon due to the inclusion of varicella vaccination in the recommended immunization schedule for children and screening for varicella immunity in HCWs during employment. We present a case report of hospital-acquired chickenpox in a patient who developed the infection during his prolonged hospital stay through a HCW who had contracted chickenpox after exposure to our patient’s roommate with herpes zoster. There was no physical contact between the roommates, but both patients had a common HCW as caregiver. The herpes zoster patient was placed in airborne precautions immediately, but the HCW continued to work and have physical contact with our patient. The HCW initially developed chickenpox 18 days after exposure to the patient with herpes zoster, and our patient developed chickenpox 17 days after the HCW. The timeline and two incubation periods, prior to our patient developing chickenpox, indicate transmission of chickenpox in the HCW from exposure to the herpes zoster patient and subsequently to our patient. The case highlights the potential for nosocomial transmission of chickenpox (varicella) to unimmunized HCWs from exposure to patients with herpes zoster and further transmission to unimmunized patients. Verification of the immunization status of HCWs at the time of employment, mandating immunity, furloughing unimmunized staff after exposure to herpes zoster, and postexposure prophylaxis with vaccination or varicella zoster immunoglobulin (Varizig) will minimize the risk of transmission of communicable diseases like chickenpox in healthcare settings. Additionally, establishing patients’ immunity, heightened vigilance and early identification of herpes zoster in hospitalized patients, and initiation of appropriate infection control immediately will further prevent such occurrences and improve patient safety.

Hepatitis E virus (HEV) is a major cause of acute jaundice in South Asia. Gaps in our understanding of transmission are driven by non-specific symptoms and scarcity of diagnostics, impeding rational control strategies. In this context, serological data can provide important proxy measures of infection. We enrolled a population-representative serological cohort of 2,337 individuals in Sitakunda, Bangladesh. We estimated the annual risks of HEV infection and seroreversion both using serostatus changes between paired serum samples collected 9 months apart, and by fitting catalytic models to the age-stratified cross-sectional seroprevalence. At baseline, 15% (95 CI: 14–17%) of people were seropositive, with seroprevalence highest in the relatively urban south. During the study, 27 individuals seroreverted (annual seroreversion risk: 15%, 95 CI: 10–21%), and 38 seroconverted (annual infection risk: 3%, 95CI: 2–5%). Relying on cross-sectional seroprevalence data alone, and ignoring seroreversion, underestimated the annual infection risk five-fold (0.6%, 95 CrI: 0.5–0.6%). When we accounted for the observed seroreversion in a reversible catalytic model, infection risk was more consistent with measured seroincidence. Our results quantify HEV infection risk in Sitakunda and highlight the importance of accounting for seroreversion when estimating infection incidence from cross-sectional seroprevalence data.

Tuberculosis (TB) in immigrants is becoming a challenge in eliminating TB in Japan. We investigated the epidemiology of TB in foreign students in Japan in 2015–2019. A total of 2007 foreign students with TB whose median age was 22.5 years (1243 (61.9%) were males) were registered. The notification rates peaked in 2016 at 164.0 per 100 000 population and decreased towards 2019. Of the 2007, 535 were from Vietnam, 444 from China and 395 from Nepal. The notification rates were 596.6 per 100 000 person-years (PYs) for Myanmar, 595.4 for the Philippines and 438.6 for Cambodia. The rates were much higher than those of the general populations in their countries of origin for Myanmar, the Philippines, Cambodia, Indonesia, Nepal, Mongolia, Vietnam and China. In comparison with the years 2010–2014, the notification rates for foreign students decreased for the students from Nepal, Vietnam and China. The TB notification rate of the foreign students in Japan can be a good surrogate indicator for the risk of TB among the immigrant subpopulation in Japan and should continuously be monitored. Those who are at higher risk of TB may be annually screened for TB to prevent TB outbreaks.

Pertussis is a highly contagious infectious disease and remains an important cause of mortality and morbidity worldwide. Over the last decade, vaccination has greatly reduced the burden of pertussis. Yet, uncertainty in individual vaccination coverage and ineffective case surveillance systems make it difficult to estimate burden and the related quantity of population-level susceptibility, which determines population risk. These issues are more pronounced in low-income settings where coverage is often overestimated, and case numbers are under-reported. Serological data provide a direct characterisation of the landscape of susceptibility to infection; and can be combined with vaccination coverage and basic theory to estimate rates of exposure to natural infection. Here, we analysed cross-sectional data on seropositivity against pertussis to identify spatial and age patterns of susceptibility in children in Madagascar. A large proportion of individuals surveyed were seronegative; however, there were patterns suggestive of natural infection in all the regions analysed. Improvements in vaccination coverage are needed to help prevent additional burden of pertussis in the country.