1. The ordinary method of calculating the birth-rate does not distinguish between the influence of fertility and of variations in conditions of the population as to age and marriage.

2. In ascertaining the true meaning of the great reduction of the birth-rate which has occured in the last 25 years it is necessary to have means for distinguishing between the accidental and the intrinsic causes of change.

3. A step in the right direction is made when the legitimate births are stated in terms of the married women at child-bearing ages, and the illegitimate births in terms of the unmarried women of the same ages.

4. This method fails to correct for the differences of fertility of the various ages comprised in the age-period 15–45.

5. By calculating standard fertility-rates for given populations McLean overcame the above difficulty, and was thus able to compare experiences of a given community at different times with the standard.

6. In this paper it is shown that by continuing the above process and obtaining corrected fertility-rates, the fertility-rates of different communities can be made directly comparable.

7. The inconveniences of this new and unfamiliar method, and the necessity involved in it of calculating the crude as well as the corrected fertility-rate in every instance, indicate the desirability of obtaining a factor for each community which throughout an entire intercensal period can be applied to the crude birth-rate of that community.

8. The desirability of such a factor is increased by the fact that the method of corrected fertility-rates does not take into account the proportion of married women in each population.

9. In this paper a method is described of obtaining factors, which, when applied to the readily available crude birth-rates, correct completely both for the varying proportion of married women in compared populations and for the varying fertility at different periods of married life.

10. The practical bearings of these corrected birth-rates will be discussed in a later paper.

Syphilis remains a serious public health problem in mainland China that requires attention, modelling to describe and predict its prevalence patterns can help the government to develop more scientific interventions. The seasonal autoregressive integrated moving average (SARIMA) model, long short-term memory network (LSTM) model, hybrid SARIMA-LSTM model, and hybrid SARIMA-nonlinear auto-regressive models with exogenous inputs (SARIMA-NARX) model were used to simulate the time series data of the syphilis incidence from January 2004 to November 2023 respectively. Compared to the SARIMA, LSTM, and SARIMA-LSTM models, the median absolute deviation (MAD) value of the SARIMA-NARX model decreases by 352.69%, 4.98%, and 3.73%, respectively. The mean absolute percentage error (MAPE) value decreases by 73.7%, 23.46%, and 13.06%, respectively. The root mean square error (RMSE) value decreases by 68.02%, 26.68%, and 23.78%, respectively. The mean absolute error (MAE) value decreases by 70.90%, 23.00%, and 21.80%, respectively. The hybrid SARIMA-NARX and SARIMA-LSTM methods predict syphilis cases more accurately than the basic SARIMA and LSTM methods, so that can be used for governments to develop long-term syphilis prevention and control programs. In addition, the predicted cases still maintain a fairly high level of incidence, so there is an urgent need to develop more comprehensive prevention strategies.

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.

Mycoplasma pneumoniae is a main pathogen causing community-acquired pneumonia in children and young adults. Since the emergence of macrolide-resistant M. pneumoniae in the early 2000s in Japan, it has been increasingly reported worldwide as a growing problem in treatment for children. With increasing macrolide-resistant M. pneumoniae and limited data regarding its characterization and molecular analysis, we investigated the dominant M. pneumoniae strains during the recent outbreak in South Korea, and evaluated if there was an association between a specific type and macrolide resistance. Between October 2014 and December 2016 in South Korea, 249 respiratory specimens obtained from patients with confirmed M. pneumoniae pneumonia were genotyped the P1 adhesin gene, and the mutations associated with resistance (A2063G and A2064G) were tested by sequencing the targeted domain V regions of the 23S ribosomal RNA gene. Results revealed that M. pneumoniae type 1 were predominant, which was strongly associated with macrolide-resistance during the whole study period. This is the first study assessing whether M. pneumoniae subtype is related to macrolide resistance during the outbreak of M. pneumoniae.

This study aimed to investigate the diverse clinical manifestations and simple early biomarkers predicting mortality of COVID-19 patients admitted to the emergency department (ED). A total of 710 patients with COVID-19 were enrolled from 6,896 patients presenting to the ED between January 2022 and March 2022. During the study period, a total of 478 patients tested positive for COVID-19, among whom 222 (46.4%) presented with extrapulmonary manifestations of COVID-19; 49 (10.3%) patients displayed gastrointestinal manifestations, followed by neurological (n = 41; 8.6%) and cardiac manifestations (n = 31; 6.5%). In total, 54 (11.3%) patients died. A Cox proportional hazards model revealed that old age, acute kidney injury at presentation, increased total leukocyte counts, low platelet counts, decreased albumin levels, and increased LDH levels were the independent predictors of mortality. The albumin levels exhibited the highest area under the curve in receiver operating characteristic analysis, with a value of 0.860 (95% confidence interval, 0.796–0.875). The study showed the diverse clinical presentations and simple-to-measure prognostic markers in COVID-19 patients presenting to the ED. Serum albumin levels can serve as a novel and simple early biomarker to identify COVID-19 patients at high risk of death.

The Department of Veterans Affairs operates a large, centrally administered health care system consisting of 173 hospitals and 4 free standing outpatient clinics nationwide with approximately 945115 hospital discharges, 24·2 million outpatient visits, and 2·86 million persons served annually over the time frame of the review. The purpose of the study was to define whether such a system could effect timely change in the incidence of tuberculosis (TB) using centralized programme planning and flexible field implementation. A retrospective review of the number of newly diagnosed cases of active TB treated at veterans health care facilities between 1 October 1990 and 30 September 1997 was determined by using a standardized annual case census.

Intervention included implementation of the most current guidelines for the prevention of transmission of TB in the community and hospital setting, including administrative and engineering controls and a change in personal protective equipment. Centrally directed programme guidance, education, and funding were provided for field use in health care facilities of widely varying size and complexity.

The numbers of total reported cases of TB decreased significantly (P < 0·001) throughout the veterans health care system (nationally and regionally), with the case rate decreasing at a rate significantly greater than that seen in the USA as a whole (P < 0·0001). TB associated with multi-drug resistance (isoniazid and rifampin) and HIV coinfection also significantly decreased over the study period. Therefore, a large, centrally administered health care system can effectively combat a re-emerging infectious disease and may also demonstrate a successful outcome greater than seen in other, perhaps less organized health care settings.

In general, it may be said that bacteria once introduced into a culture of trypanosomes tend to outgrow and check the development of the flagellates. In exceptional instances, however, the bacteria thus introduced exert little of no interference and may be even apparently beneficial. While in the former case the trypanosomes soon die out, in the latter instance the mixed cultures may be kept for six months or longer.

Two single-tube media, lactose-tryptone-lauryl sulphate broth (LTLSB) and lauryl-tryptose-mannitol broth were tested in parallel in a series of 1111 tests on water samples from a variety of sources.

LTLSB was found to be superior both in gas and indole production from Escherichia coli when incubated at 44 °C and is recommended as the most suitable single-tube confirmatory test for this organism.

In the first report (vol. vi. p. 450) we described several series of experiments which had as their object the determination of the relative importance of the Indian rat flea, Palex cheopis, and of actual close contact in the absence of fleas in the dissemination of plague from animal to animal. These observations were carried out in a series of small godowns or cabins, which were built especially for the purpose. The experiments which we have now to put on record are a continuation of those already published. They were carried out during the non-plague season of 1906 and the plague season of 1907.

A subclinical infection of Salmonella typhimurium in a broiler flock was investigated and attempts were made to eradicate the infection by treatment with furazolidone. One-quarter of the chickens were still infected after they had been through the processing plant. Washing in heavily chlorinated water reduced the number of contaminated carcasses. Infected chickens were also found in four other companion flocks on the same farm.

A survey of both the prevailing and the desirable conditions for housing small laboratory animals, with particular reference to rats and mice, is described. The data surveyed are confined to laboratories in Great Britain and include requirements of space, heating, ventilation and building construction, with such accessories as cages, feeding devices and other equipment.

Pus from a lumbar abscess in a boy, aged 10 years, produced severe general tuberculosis in a guinea-pig. A culture from this guinea-pig resembled a bovine strain in primary culture on egg and a eugonic human strain in subculture on glycerine egg and glycerinated potato. The virulence of the strain was high for the guinea-pig and irregular for the rabbit. For some rabbits the pathogenic effects of the strain were much more severe than those of typical human bacilli and approached, but did not equal, those of bovine bacilli. The results in other rabbits were similar to those of eugonic human bacilli. Cultures recovered from the rabbits resembled in characters the original strain, which was therefore not a mixture of the human and bovine types of tubercle bacilli. The strain cannot be described as ‘human’ or ‘bovine’ according to the usually accepted distinction between these types in the rabbit, but according to the results in the vole could be classified as belonging to the human type.

(1) These experiments prove that the fumigator is safer to use than the dumping fixture, because high concentrations of the poison gas are avoided, so that dangerous pockets are not developed.

(2) The poison gas is more evenly distributed over the different parts of the section of the ship under treatment.

(3) High concentrations, however, can be developed^ at will in any part which requires special attention.

(4) The maximum concentrations of the poison gas were obtained in every part of the section in a shorter time, when the fumigator was used, than when the dumping fixture was employed.

(5) The artificial ventilation caused by the fan, which is capable of blowing into the section 500 to 1000 cubic feet of fresh air per minute, according to the speed of the motor, materially assists the rapid clearing of the poison gas from the ship, after it has accomplished its work. It is thus possible to complete the fumigation and ventilation of a ship in 3 hours using the cyanide fumigator, while more than 4 hours are required for the dumping fixture.

(6) Even more important is the fact that smaller quantities of cyanide can be used with greater efficiency in the fumigator, than larger quantities, with less efficiency in the dumping fixture.

(7) The general conclusion is arrived at, that, from the point of view of efficiency, safety and economy, the fumigator is superior to the dumping fixture. Creel has shown that, in respect to the time required for completing the fumigation, and in respect to the thoroughness of the process, both in killing rats and insects, the dumping fixture is superior to the Clayton gas machine. It follows, therefore, that the cyanide fumigator is very much superior in these respects to the Clayton gas machine.

Two hundred and fifty clinical strains of Candida albicans and six isolates from a cross-infection outbreak were studied for their ability to assimilate 19 carbohydrates in the API-20C system (API Laboratory Products Ltd., Basingstoke, UK). The assimilation profiles were stable on repeat testing; at intervals in the 72 h duration of the test; and when incubated at different temperatures.

Although not a complete system of biotyping, the API-20C system shows high typability, and fair reproducibility and discrimination, having a limited role in indicating which isolates should be typed by more elaborate methods.

1. A clinical and biochemical study of a group of thirty patients from northern Portugal shows that they were suffering from a mild form of pellagra with no signs of severe malnutrition or of associated deficiencies except dental abrasion caries and pyorrhoea.

2. The diet of these patients in most respects was chemically satisfactory. Apart from a very low consumption of animal protein the gross intake of calories, total protein minerals and vitamins, including nicotinic acid, was satisfactory.

3. Since the syndrome was completely cured by nicotinic acid, it is suggested that the main characteristic of a diet on which pellagra is likely to develop is not a shortage of nicotinic acid, but a lack of high-grade protein.

4. A maize diet, satisfactory so far as calories and total protein are concerned, may produce pellagra because maize proteins are short of certain essential amino-acids. Other cereal diets may also produce pellagra if the general level of nutrition is very low.

5. The syndrome may be cured either by very large doses of nicotinic acid without change of diet or by moderate doses accompanied by abundant animal protein.

The following paper gives some results of a series of experiments on the bactericidal power of various sources of ultra-violet radiation. The “power” of the source was in each case measured by the quartz-cadmium photo-electric cell described by the authors (1925), and it is shown that very definite and practically useful correlations exist between the cell reading and this typical abiotic action.

This paper deals with the result obtained after testing, by the “Dick” method, the susceptibility of a series of adults to scarlet fever toxin. The toxin used was produced by the Wellcome Physiological Research Laboratory. While various strengths of solutions were tried to begin with from 1:2500 to 1:250, no advantage was found to result from the use of a solution stronger or weaker than 1:1000. The tests were, therefore, carried out with the standard “Dick” toxin as supplied by this firm.

Space-time interaction analysis was applied to data from 101 elementary school children who contracted variola minor during an epidemic in Bragança Paulista County, Brazil. One school had two and the other three shifts of students occupying the same classrooms each day. There was no evidence found for excessive numbers of cases to occur among unvaccinated students occupying the same desks or seated near the desks occupied by cases occurring during another shift. Only three cases occurred among the 31 unvaccinated students occupying desks of students with variola from other shifts. Only one of these three subsequent cases occurred at a time interval suggestive of transmission. For the three models tested there was no evidence of space-time interaction between time of onset of the disease and location of desk for pairs of students from different shifts.

A new form of photo-electric photometer or colorimeter is described which permits of accurate and objective readings in a wide range of colorimetric work with small quantities of solutions. The instrument is of the null-point type and hence requires calibration to suit the particular estimation.

The writer is indebted to the Earl of Moray Fund of the University of Edinburgh for financial assistance towards the expenses of the earlier part of the work.

The original model was made by A. H. Baird of Edinburgh, the model described above by Wm. Watson and Sons, London, to whom, and to Mr W. E. Watson-Baker, I am indebted for suggestions on a number of points.