A probability nomogram to predict rectal temperature in children

Postvaccination Fever Response Rates in Children Derived Using the Fever Coach Mobile App: A Retrospective Observational Study

BACKGROUND

Postvaccination fever is a mild adverse event that naturally improves without complications, but is highly prevalent and can be accompanied by febrile convulsions in some cases. These adverse effects may cause parents to delay or avoid vaccinating their children.

OBJECTIVE

This study aimed to identify postvaccination fever patterns and the ability of antipyretics to affect changes in these patterns from data collected from a mobile app named Fever Coach.

METHODS

Data provided by parents of feverish children derived from a mobile app, Fever Coach, were used to identify postvaccination fever patterns according to vaccinations and the use of antipyretic drugs. We selected single vaccination records that contained five or more body temperature readings performed within 48 hours of vaccination, and we analyzed postvaccination fever onset, offset, duration, and maximum body temperature. Through observing the postvaccination fever response to vaccination, we identified the effects of antipyretic drugs on postvaccination fever onset, offset, and duration times; the extent of fever; and the rate of decline. We also performed logistic regression analysis to determine demographic variables (age, weight, and sex) involved in relatively high fevers (body temperature ≥39°C).

RESULTS

The total number of Fever Coach users was 25,037, with 3834 users having entered single vaccination records, including 4448 vaccinations and 55,783 body temperature records. Most records were obtained from children receiving the following vaccinations: pneumococcus (n=2069); Japanese encephalitis (n=911); influenza (n=669); diphtheria, tetanus, and pertussis (n=403); and hepatitis A (n=252). According to the 4448 vaccination records, 3427 (77.05%) children had taken antipyretic drugs, and 3238 (89.15%) children took antibiotics at body temperatures above 38°C. The number of children taking antipyretics at a body temperature of 38°C was more than four times that of those taking antipyretics at 37.9°C (307 vs 67 cases). The number of instances in which this temperature threshold was reached was more than four times greater than the number when the temperature was 37.9°C. A comparative analysis of antipyretic and nonantipyretic cases showed there was no difference in onset time; however, offset and duration times were significantly shorter in nonantipyretic cases than in antipyretic cases (P<.001). In nonantipyretic cases, offset times and duration times were 9.9 and 10.1 hours shorter, respectively, than in antipyretic cases. Body temperatures also decreased faster in nonantipyretic cases. Influenza vaccine-associated fevers lasted relatively longer, whereas pneumococcus vaccine-associated fevers were relatively short-lived.

CONCLUSIONS

These findings suggest that postvaccination fever has its own fever pattern, which is dependent on vaccine type and the presence of antipyretic drugs, and that postvaccination temperature monitoring may ease fever phobia and reduce the unnecessary use of antipyretics in medical care.

Immunogenicity and safety study of a new DTaP-IPV-Hep B-PRP-T combined vaccine compared to a licensed DTaP-IPV-Hep B//PRP-T comparator, both concomitantly administered with a 7-valent pneumococcal conjugate vaccine at 2, 4, and 6 months of age in Thai infants

OBJECTIVE

To assess a new, fully-liquid, hexavalent DTaP-IPV-Hep B-PRP-T vaccine (diphtheria toxoid (D), tetanus toxoid (T), acellular pertussis (aP), inactivated poliovirus (IPV), hepatitis B (Hep B), and Haemophilus influenzae type b polysaccharide conjugated to tetanus protein (PRP-T) antigens) compared to a licensed DTaP-IPV-Hep B//PRP-T vaccine following primary series co-administration with a 7-valent pneumococcal conjugate vaccine (PCV7).

METHODS

This was a randomized, phase III, observer-blind study in Thai infants (N=412), who received DTaP-IPV-Hep B-PRP-T or DTaP-IPV-Hep B//PRP-T at 2, 4, and 6 months of age, co-administered with PCV7. All received Hep B at birth. Non-inferiority for Hep B ≥ 10 mIU/ml and PRP ≥0.15μg/ml was analyzed (DTaP-IPV-Hep B-PRP-T relative to DTaP-IPV-Hep B//PRP-T) at 1 month post-primary. Seroprotection/seroconversion and geometric mean titers (GMTs) were analyzed descriptively for all hexavalent components. Safety was evaluated from parental reports.

RESULTS

Anti-Hep B and anti-PRP antibody seroprotection rates were high for DTaP-IPV-Hep B-PRP-T (n=189) and DTaP-IPV-Hep B//PRP-T (n=190), and non-inferiority was demonstrated. Anti-D and anti-T ≥ 0.01 IU/ml, anti-polio types 1, 2, and 3 ≥ 8 (1/dil), and anti-PT and anti-FHA seroconversion were high and similar in each group. For DTaP-IPV-Hep B-PRP-T and DTaP-IPV-Hep B//PRP-T, anti-Hep B ≥ 100 mIU/ml was 98.4% and 99.5% (GMTs 2477 and 2442 mIU/ml), respectively; anti-PRP ≥ 1.0 μg/ml was 85.2% and 71.1% (GMTs 5.07 and 2.41 μg/ml), respectively. Safety profiles were comparable. There were no vaccine-related serious adverse events.

CONCLUSIONS

Following co-administration with PCV7 the investigational DTaP-IPV-Hep B-PRP-T vaccine was safe and immunogenic. Non-inferiority to DTaP-IPV-Hep B//PRP-T was shown for Hep B and PRP.

Fever after Immunization: Current Concepts and Improved Future Scientific Understanding

Fever is a common clinical complaint in adults and children with a variety of infectious illnesses, as well as a frequently reported adverse event following immunization. Although the level of measured temperature indicative of a "fever" was first defined in 1868, it remains unclear what role fever has as a physiologic reaction to invading substances, how best to measure body temperature and compare measurements from different body sites, and, consequently, how to interpret fever data derived from vaccine safety trials or immunization safety surveillance. However, even with many aspects of the societal, medical, economic, and epidemiologic meanings of fever as an adverse event following immunization (AEFI) still elusive, it is a generally benign--albeit common--clinical sign. By standardizing the definition and means of assessment of fever in vaccine safety studies, thereby permitting comparability of data, we hope to arrive at an improved understanding of its importance as an AEFI.

An assessment of infrared tympanic thermometers for body temperature measurement

This article provides an experimental assessment of three commercially available clinical thermometers, using different thermal infrared sensors. This kind of thermometer measures body temperature by detecting infrared radiation from the tympanic membrane. These thermometers are growing in popularity thanks to their simplicity of use, rapid response and minimal distress to the patient. The purpose of the laboratory tests presented here was to assess the effect of varying ambient temperature and varying simulated patient temperature on the performance of the three infrared tympanic thermometers.