Poliomyelitis in pregnancy

Acute poliomyelitis occurs in all trimesters of pregnancy. At one time there were six women in the poliomyelitis ward at Children's Hospital, five of whom were either pregnant or recently delivered. Poliomyelitis is an important entity in the differential diagnosis of diseases complicating pregnancy. Once diagnosed, treatment is directed primarily toward the symptoms of poliomyelitis, secondarily toward pregnancy. Effort should be made to maintain adequately high oxygen tension in the maternal blood stream to protect the fetus. The prognosis of the disease when it occurs during pregnancy may be less predictable, but it is generally good for both mother and infant. Although the incidence of abortion is relatively high, if the pregnancy goes to term parturition is expected to be normal. The number of cases reported is not sufficient to establish the significance of the suspected selective occurrence of poliomyelitis in pregnancy.     

Clinical Surveillance After Feeding Oral Attenuated Live Polio Vaccine

During widespread administration of oral poliomyelitis vaccine in the United States and Canada, a number of neurological conditions occurring within 30 days of vaccine administration were reported. After careful investigation, 11 cases of paralytic poliomyelitis in the United States and four cases in Canada have been accepted as being most probably vaccine-associated.The case of a 35-year-old man who developed paralytic poliomyelitis 17 days after taking oral vaccine is reported. Type III Poliovirus was isolated from his stools, and subsequent virological investigation of this virus strain suggested that it most likely was the attenuated strain. The McBride test gave an NK value of 90 and the rct/40 marker was positive. A rise in Type III antibodies was found in the patient''s serum, and increased neurovirulence was demonstrated by intracerebral inoculation of monkeys.Since many cases of neurological involvement have not been accepted as vaccine-associated because of the lack of adequate early investigations, active clinical surveillance after oral polio vaccine administration is urged, and appropriate studies should be carried out in suspect neurological complications.     

Formula feeding can help illuminate long-term consequences of full ectogenesis

Breastfeeding is analogous to pregnancy as an experience, in its exclusiveness to women, and in its cost and the effects it has on equitable share of labor. Therefore, the history of formula feeding provides useful insights into the future of full ectogenesis, which could evolve into a more severe version of what formula feeding is today: simplify life for some women and provide couples with a more equitable share of work at the cost of stigma, guilt and a daily diet of studies purporting to show the benefits of natural pregnancy. Making pregnancy an optional route to motherhood would make women's life trajectory more similar to men's and thus put pressure on women to compete with men on the ground shaped by men's preferences. Despite being a treasured experience of many women today, bearing children could become the luxury of the few, the province of the very poor and a choice working women will pay a high price for as women who choose pregnancy become stigmatized as self-indulgent or unprofessional and penalized for it in the workplace. At the same time, scarce societal resources that could be used to support pregnant women and working mothers would instead be directed toward proving to women or even forcing them to gestate children “the right way.” While not necessarily threatening on its own, when added to formula feeding, IVF, stem-cell produced ova and sex robots, full ectogenesis could diminish men's stake in women's wellbeing and even existence.     

Understanding the Complexity of Ambivalence Toward Pregnancy: Does It Predict Inconsistent Use of Contraception?

Ambivalence towards future pregnancy is common and may increase the risk of unprotected sex and unintended pregnancy. We propose that ambivalent attitudes toward pregnancy consist of subtypes that are differentially associated with contraceptive use. Using data from a nationally representative survey of unmarried young adults (N = 1,147), we constructed four categories of ambivalence based on attitudes toward a hypothetical pregnancy. Multivariate analyses examined characteristics of ambivalence and the association between ambivalence and contraceptive use. Approximately one third of sexually active unmarried young adults are ambivalent about pregnancy. Having positive ambivalence (important to avoid a pregnancy but would be happy if it occurred) is associated with age, gender, education, and Hispanic origin. Although ambivalence toward pregnancy is associated with lower contraceptive use, this is true only among women with negative ambivalence (not important to avoid a pregnancy but would be unhappy if a pregnancy occurred). Attitudes toward pregnancy are multifaceted, and a more nuanced understanding of women’s attitudes toward pregnancy can help target prevention programs and related policies for women at risk of unintended pregnancy.     

Outside Europe. Is poliomyelitis a serious problem in developing countries?--the Danfa experience.

Children were examined for lameness in the Danfa Project district of rural Ghana to assess the impact of endemic poliomyelitis and to test a widely held hypothesis that paralytic poliomyelitis is relatively rare in such districts (less than 1 per 1000 children affected). The observed prevalence of lameness attributable to poliomyelitis was 7 per 1000 school-aged children, and the annual incidence is estimated to be at least 28 per 100 000 population. Although no evidence for an epidemic was found, these rates are comparable with those in the USA and Europe during the years of severe epidemics and indicate that a high price is being paid in the Danfa district for the natural acquisition of immunity. As a result, immunisation against poliomyelitis has been given high priority. A teacher questionnaire was also tested for use in postal surveys as a rapid means of estimating the prevalence of lamenes attributable to poliomyelitis in countries with a reasonable network of primary schools.     

RELATION OF A STREPTOCOCCUS TO EPIDEMIC POLIOMYELITIS—Studies in Etiology,Diagnosis and Specific Treatment

The production in 1915 of herpes zoster or “posterior” poliomyelitis in animals with a streptococcus led to further research on the etiologic importance of streptococci in “anterior” poliomyelitis.A specific streptococcus was demonstrated consistently in persons with poliomyelitis and in well persons having contact with them or merely inhabiting an area in which poliomyelitis was epidemic. That the organism was not present in areas remote from contact with the disease was likewise demonstrated.The streptococcus has been isolated from filtrates of poliomyelitis virus and from the tissues and exudates which harbor the virus. It appears in the spinal fluid in the preparalytic stage of poliomyelitis and disappears from the spinal fluid during the severe stage of the disease.Antibody and antigen prepared from the streptococcus were used to determine the presence of antigen and antibody indicative of streptococcal infection in many patients with poliomyelitis and in well persons. The intensity of reaction indicating specific streptococcal antigen was directly proportional to the degree of paralysis in patients; the reaction was greater in persons whose age, sex and previous isolation from the disease would normally indicate greater susceptibility. The test for antibody gave opposite results.Specific agglutinins for the streptococcus and neutralizing antibody for the virus were present consistently in the serum of persons and monkeys during recovery from poliomyelitis.Virus produced in vitro from the associated streptococcus caused all the clinical and pathologic features of poliomyelitis in monkeys inoculated with it, and the animals that recovered from the disease thus induced were proved to be immune thereafter to the natural virus.Antistreptococcic serum prepared in horses was used to treat poliomyelitis. In a group of monkeys inoculated with the virus of the disease, 6 per cent of those receiving the serum before inoculation died of the disease; of the control group, 82 per cent. In a series of poliomyelitis patients treated with the serum the mortality rate was 8 per cent; in a control series, 21 per cent. In a series treated in all stages of the disease by the author, 10 per cent died; of those who did not receive the serum, 25 per cent.An antibody has been prepared from the streptococcus which appears to prevent paralysis and otherwise mitigate poliomyelitis and to provide immunization from the disease.The conclusion is reached that the virus of poliomyelitis is a form of the specific streptococcus, which is the agent in primary infections and in the development of the immunizing antibody.     

Incidence of poliomyelitis; the effect of tonsillectomy and other operations on the nose and throat

A statistical survey was made of all the cases of poliomyelitis occurring in all of Los Angeles County during the three years of 1949, 1950 and 1951 in an attempt to determine the effect of operations on the nose and throat on the incidence of poliomyelitis. Tonsillectomy and adenoidectomy were the only operations noted with any degree of frequency. Yet, in the total of 3,601 cases of poliomyelitis that occurred in this three-year period there were only 20 (0.55 per cent) in which the patient had had recent tonsillectomy and adenoidectomy. The incidence of this disease in patients who had had tonsillectomy and adenoidectomy was compared with the "expected" incidence as determined from the incidence in other patients, in the same age group. There was no significant difference between actual and expected incidence even during the summer months when most cases of poliomyelitis occurred. The same was true with regard to recently tonsillectomized patients in the epidemic months of July through October. In a separate survey of 675 patients with poliomyelitis, it was noted that only 30 per cent ever had had tonsillectomy or adenoidectomy. Inasmuch as it is estimated that one of every three persons in the general young population nowadays has had tonsillectomy and adenoidectomy, this figure is no more or less than could be expected.     

RELATION OF A STREPTOCOCCUS TO EPIDEMIC POLIOMYELITIS-Studies in Etiology,Diagnosis and Specific Treatment

The production in 1915 of herpes zoster or "posterior" poliomyelitis in animals with a streptococcus led to further research on the etiologic importance of streptococci in "anterior" poliomyelitis.A specific streptococcus was demonstrated consistently in persons with poliomyelitis and in well persons having contact with them or merely inhabiting an area in which poliomyelitis was epidemic. That the organism was not present in areas remote from contact with the disease was likewise demonstrated.The streptococcus has been isolated from filtrates of poliomyelitis virus and from the tissues and exudates which harbor the virus. It appears in the spinal fluid in the preparalytic stage of poliomyelitis and disappears from the spinal fluid during the severe stage of the disease. Antibody and antigen prepared from the streptococcus were used to determine the presence of antigen and antibody indicative of streptococcal infection in many patients with poliomyelitis and in well persons. The intensity of reaction indicating specific streptococcal antigen was directly proportional to the degree of paralysis in patients; the reaction was greater in persons whose age, sex and previous isolation from the disease would normally indicate greater susceptibility. The test for antibody gave opposite results. Specific agglutinins for the streptococcus and neutralizing antibody for the virus were present consistently in the serum of persons and monkeys during recovery from poliomyelitis. Virus produced in vitro from the associated streptococcus caused all the clinical and pathologic features of poliomyelitis in monkeys inoculated with it, and the animals that recovered from the disease thus induced were proved to be immune thereafter to the natural virus. Antistreptococcic serum prepared in horses was used to treat poliomyelitis. In a group of monkeys inoculated with the virus of the disease, 6 per cent of those receiving the serum before inoculation died of the disease; of the control group, 82 per cent. In a series of poliomyelitis patients treated with the serum the mortality rate was 8 per cent; in a control series, 21 per cent. In a series treated in all stages of the disease by the author, 10 per cent died; of those who did not receive the serum, 25 per cent. An antibody has been prepared from the streptococcus which appears to prevent paralysis and otherwise mitigate poliomyelitis and to provide immunization from the disease.The conclusion is reached that the virus of poliomyelitis is a form of the specific streptococcus, which is the agent in primary infections and in the development of the immunizing antibody.     

Respiratory poliomyelitis: a follow-up study.

Data from the medical records of 113 patients living in Manitoba who had contracted respiratory poliomyelitis between 1952 and 1959 were compared with information obtained from interviews with these patients in 1980. The study was designed to determine whether the patients'' respiratory function, mobility, ability to perform daily tasks, and employment, residential and marital status had changed between 1 year after the onset of polio and 1980. The patients'' dependence on mechanical aids and other people was also studied. More than half (56%) of the patients perceived their respiratory impairment to be the same as it was 1 year after the onset of polio, 27% perceived the impairment to be increased, and 17% perceived it to be decreased. There was an association between level of respiratory function, mobility and ability to perform daily tasks. The 69 patients who lived at home had better respiratory function, mobility and ability to perform daily tasks than the 24 patients who were assisted by a home care program and the 20 who lived in hospital. The latter group had the lowest levels of respiratory and functional ability.     

Maternal Th1- and Th2-type reactivity to placental antigens in normal human pregnancy and unexplained recurrent spontaneous abortions.

Spontaneous abortion is the most common complication of pregnancy, but the etiology of a significant proportion of abortions is still unknown. We have examined the production of Th1- and Th2-type cytokines by women with unexplained recurrent spontaneous abortion (RSA) since it appears that successful murine pregnancy occurs in a Th2-dominant situation and that Th1-type immunity is associated with pregnancy failure. We have compared maternal reactivity toward placental antigens in women with a history of successful pregnancy with that in women with a history of RSA. This was done by coculturing maternal peripheral blood mononuclear cells (PBMC) with autologous placental cells and also by stimulating maternal PBMC with antigens from a choriocarcinoma cell line of trophoblastic origin. We detected significantly greater levels of the Th2 cytokines IL-6 and IL-10 in normal pregnancy compared to unexplained RSA and significantly higher levels of the Th1 cytokine IFN-gamma in RSA compared to normal pregnancy. These results suggest that women with normal pregnancy have a higher Th2 bias, while women with a history of RSA evince a bias toward Th1-type reactivity.     

Pre-implantation Pregnancy Disruption in Female Meadow Voles Microtus pennsylvanicus (Rodentia: Muridae): Male Competition or Female Mate Choice?

I investigated alternative hypotheses concerning the functions of pre-implantation male-induced pregnancy disruption in meadow voles. Disruptions may be viewed as: 1. Postcopulatory male competition; 2. A mechanism for postcopulatory mate choice by females; and 3. A means of benefitting females by terminating investment in litters that may be harmed by new males. Female voles were paired with a second male 3 d after mating with their first mate. Behavioural interactions between the female and each male were compared for females that disrupted or retained the pregnancy sired by the first male. Whether they were the females' first or second mates, males siring litters showed similar high levels of approach and moderately high aggression, behaviour that differed from the females' other mates. Disrupted females huddled sooner with their second mates than females that retained their original pregnancies, and females tended to approach males that approached them. These results suggest that females influence whether a disruption occurs by the amount of contact they initiate with the second male, and thus pregnancy disruption may facilitate postcopulatory mate choice by females. This pre-implantation disruption did not enhance female reproductive success: pup survival was the same whether or not a disruption occurred, and males living with pups they had sired (after a disruption) spent as much time with them as males with unrelated pups (females did not disrupt).     

Epidemicity of poliomyelitis; possible role of seasonal variation in food quality

Seasonal variations occur in the phosphate, phospholipid and protein content of foods. The lower content occurs in the dry season. This is most often in the summer and fall months, which is the usual time of year for epidemics of poliomyelitis. Question is raised as to whether epidemics of poliomyelitis are a consequence of the host-virus balance being shifted in favor of the virus during this season because of the lower nourishing power of foods common to the daily diet.     

A statistical model of the international spread of wild poliovirus in Africa used to predict and prevent outbreaks

Background

Outbreaks of poliomyelitis in African countries that were previously free of wild-type poliovirus cost the Global Polio Eradication Initiative US$850 million during 2003–2009, and have limited the ability of the program to focus on endemic countries. A quantitative understanding of the factors that predict the distribution and timing of outbreaks will enable their prevention and facilitate the completion of global eradication.

Methods and Findings

Children with poliomyelitis in Africa from 1 January 2003 to 31 December 2010 were identified through routine surveillance of cases of acute flaccid paralysis, and separate outbreaks associated with importation of wild-type poliovirus were defined using the genetic relatedness of these viruses in the VP1/2A region. Potential explanatory variables were examined for their association with the number, size, and duration of poliomyelitis outbreaks in 6-mo periods using multivariable regression analysis. The predictive ability of 6-mo-ahead forecasts of poliomyelitis outbreaks in each country based on the regression model was assessed. A total of 142 genetically distinct outbreaks of poliomyelitis were recorded in 25 African countries, resulting in 1–228 cases (median of two cases). The estimated number of people arriving from infected countries and <5-y childhood mortality were independently associated with the number of outbreaks. Immunisation coverage based on the reported vaccination history of children with non-polio acute flaccid paralysis was associated with the duration and size of each outbreak, as well as the number of outbreaks. Six-month-ahead forecasts of the number of outbreaks in a country or region changed over time and had a predictive ability of 82%.

Conclusions

Outbreaks of poliomyelitis resulted primarily from continued transmission in Nigeria and the poor immunisation status of populations in neighbouring countries. From 1 January 2010 to 30 June 2011, reduced transmission in Nigeria and increased incidence in reinfected countries in west and central Africa have changed the geographical risk of polio outbreaks, and will require careful immunisation planning to limit onward spread. Please see later in the article for the Editors'' Summary     

Mechanism of Injury-Provoked Poliomyelitis

Skeletal muscle injury is known to predispose its sufferers to neurological complications of concurrent poliovirus infections. This phenomenon, labeled “provocation poliomyelitis,” continues to cause numerous cases of childhood paralysis due to the administration of unnecessary injections to children in areas where poliovirus is endemic. Recently, it has been reported that intramuscular injections may also increase the likelihood of vaccine-associated paralytic poliomyelitis in recipients of live attenuated poliovirus vaccines. We have studied this important risk factor for paralytic polio in an animal system for poliomyelitis and have determined the pathogenic mechanism linking intramuscular injections and provocation poliomyelitis. Skeletal muscle injury induces retrograde axonal transport of poliovirus and thereby facilitates viral invasion of the central nervous system and the progression of spinal cord damage. The pathogenic mechanism of provocation poliomyelitis may differ from that of polio acquired in the absence of predisposing factors.     

USE OF THE ROCKING BED TO AUGMENT VENTILATION IN PATIENTS WITH POLIOMYELITIS

As the first step in an attempt to clarify criteria for use of the rocking bed rather than the respirator as an aid to breathing for patients with weakness of respiratory muscle function caused by poliomyelitis, ventilation studies were done on seven patients with pronounced weakness or paralysis of the respiratory muscles. Average tidal air volume was considerably less when the patient was on the rocking bed than when he was in the respirator. Since the tidal air volume with the patient on the rocking bed represents the maximum that can be produced with the apparatus, whereas the volume in the respirator represents the patient''s usual tidal air and the respirator is capable of a greater volume if necessary, it is apparent that in cases of complete paralysis of the respiratory muscles the respirator has a large margin of safety, the rocking bed none.From clinical observations made on 51 patients who were put upon the rocking bed—23 of them early in the course of the disease and 28 after they had been ill three months or more—it was concluded that the rocking bed is contraindicated for patients who are febrile and in whom the disease is progressing rapidly, and for those with atelectasis or urinary or pulmonary infection. It must be used with extreme care in the case of patients early in the course of the disease who are not tracheotomized, because of a tendency toward increased accumulation of mucus and the danger of atelectasis.General guides were developed with regard to use of the rocking bed for patients with post-acute poliomyelitis, and somewhat different rules were drawn for use of the apparatus in cases in which there is a chronic respiratory problem.The rocking bed will give artificial respiration in cases of respiratory weakness, but will not provide enough tidal air for the patient with paralysis of the muscles of respiration.     

The level of postvaccinal immunity to diphtheria, tetanus and poliomyelitis in relation to the number of inoculations]

The work was aimed at the comparative study of the intensity of immunity to diphtheria, tetanus and poliomyelitis, depending on the number of injections of adsorbed diphtheria-pertussis-tetanus (DPT) vaccine and poliomyelitis vaccine, for the purpose of finding out the possibility of reducing the antigenic load given to children without diminishing the intensity of immunity. To determine the level of immunity to diphtheria and tetanus, 1900 children under school age were serologically studied by the micromethod in the passive hemagglutination test. The intensity of immunity to poliomyelitis virus was studied in 333 children by means of the neutralization test. The immunogenic properties of the diphtheria component of adsorbed DPT vaccine were found to be less pronounced than those of the tetanus component of the vaccine, which made it impossible to reduce the antigenic load by decreasing the number of vaccinations against diphtheria. The results of the study of postvaccinal immunity to poliomyelitis suggest that during the first and second year of life the course of vaccination against poliomyelitis may be reduced to 3 injections.     

Simultaneous Immunization with B.C.G., Diphtheria-tetanus,and Oral Poliomyelitis Vaccines in Children Aged 13-14

The simultaneous administration of B.C.G. vaccine, diphtheria-tetanus toxoid aluminium hydroxide adsorbed vaccine, and oral poliovaccine was studied in 628 children aged 13-14 years between 1966 and 1969 in Newham, London. The efficacy of these vaccines was unaffected by administering them at the same time; routine simultaneous administration is considered justified when organizational difficulties prevent the attainment of high immunization rates with the vaccines given separately. No adverse reactions to B.C.G. or oral poliomyelitis vaccines took place, but 8% of children had moderately severe local reactions after diphtheria-tetanus aluminium hydroxide adsorbed vaccine, which were attributed to diphtheria toxoid.Serological studies showed the need for immunization against diphtheria, tetanus, and poliomyelitis at 13-14 years of age. Because of the adverse reactions to diphtheria toxoid, however, simultaneous administration of tetanus toxoid aluminium hydroxide adsorbed, oral poliomyelitis, and B.C.G. vaccines only is recommended at present.An “adult type” diphtheria-tetanus toxoid might overcome the problem of reactions, though in two to three years'' time most children aged 13-14 years will have received diphtheria-tetanus-pertussis vaccine in infancy and reinforcement might then be accomplished by a small intradermal dose of the currently available fluid diphtheria-tetanus vaccine.Continued serological studies of diphtheria and tetanus antitoxins and polio antibody are necessary to determine the future need for reinforcement of immunity; such studies should become an essential part of the surveillance of the community immunization programme.     

Strain-specific antibodies as an indicator of the circulation of wild poliomyelitis viruses and their role in the formation of collective immunity in the population

Essential differences in the intensity of collective immunity to poliomyelitis in the donors of Moscow and Kaluga were established. To find out the nature of high characteristics of collective immunity to poliovirus, types 1 and 2, in the donors of Kaluga, strain-specific antibodies to wild and vaccine polioviruses were studied. In a considerable number of donors strain-specific antibodies to poliovirus, types 1 and 2, were detected. This made it possible to presume a sufficiently wide circulation of these viruses among the population of the city in the middle of the 20th century and, as a consequence, high level of collective immunity appeared. Strain-specific antibodies to poliovirus of type 3 were rarely detected. This made it possible to suggest that the circulation of viruses of this type among the population was limited. Immunity to viruses of this type was due only to immunization. For this reason the characteristics of collective immunity in the donors of Moscow and Kaluga coincided. The detection of strain-specific antibodies to poliomyelitis virus allowed to retrospectively form the opinion of the spread and time of the circulation of wild poliomyelitis viruses in the population.     

Major Operations on Patients with Poliomyelitic Impairment

Pertinent data on operations (other than orthopedic) carried out in 39 patients who had residual impairment from poliomyelitis were reviewed with a view to appraising what additional operative risk there may be for such patients.For a large proportion of the patients, equipment to aid respiration was needed and a large proportion of the operations were urologic procedures as might be expected in a group with generally restricted physical activity. Also, the occurrence of complications was higher than for an ordinary surgical service. Even so, the experience indicated that residual impairment from poliomyelitis ought not be considered a contraindication even of elective, let alone emergency operations.     

Long‐Term Weight Development in Women: A 15‐Year Follow‐up of the Effects of Pregnancy

Objective: The aim of this study was to evaluate how well prepregnancy BMI, gestational weight gain, and postpartum weight retention predict retention of weight 15 years later among parous women. Research Methods and Procedures: The Stockholm Pregnancy and Women's Nutrition (SPAWN) study is a long‐term follow‐up study of women who delivered children in 1984 to 1985 (n = 2342). The participants initially filled out questionnaires about their eating and exercise habits, social circumstances, etc. before, during, and at 1 year after pregnancy. Anthropometric data were also sampled. Fifteen years later, these women were invited to take part in the follow‐up study. Anthropometric measurements were collected, and similar questions were asked. Five hundred sixty‐three women participated in the SPAWN 15‐year follow‐up study. The sample was divided into groups to examine three presumably critical time periods: 1) overweight and normal weight before pregnancy; 2) low, intermediate, and high weight gainers during pregnancy; and 3) low, intermediate, and high weight retainers at 1 year after pregnancy. Results: The overweight women did not gain more weight during pregnancy or retain more weight at 1 year follow‐up. High weight gainers during pregnancy retained more weight at the 1‐year and the 15‐year follow‐ups. High weight retainers had gained more during pregnancy and retained it at the 15‐year follow‐up. Fifty‐six percent of the high weight gainers during pregnancy ended up in the high weight retainers group. Discussion: Women who are overweight before pregnancy do not have a higher risk of postpartum weight retention than normal weight women. Thus, it is not necessarily the initially overweight woman who should be the target or focus of weight control programs during or after pregnancy. Both high weight gainers and high weight retainers had higher BMI at the 15‐year follow‐up, although only 56% of the high weight gainers during pregnancy were also classified as high weight retainers at the 1‐year follow‐up. Weight retention at the end of the postpartum year predicts future overweight 15 years later.