Acute undifferentiated febrile illnesses (AUFIs), account for considerable morbidity, mortality and economic burden in resource poor country like India during the monsoon season. The term Acute Undifferentiated Fever (AUF)  is used to denote fevers that usually do not extend beyond a fortnight, and lack localizable or organ-specific clinical features.  It   typically includes   fever, without any localized source of infection, of 14 days or less in duration. Myalgia, arthralgia, headache, altered sensorium, and jaundice were considered not to have localizing values [1].

During the past 20 years, there has been a dramatic emergence and re-emergence of viruses, bacteria and parasitic infections, including novel pathogens as well as those previously believed to be under control. Many of these pathogens cause acute undifferentiated febrile illness (AUFI, or acute febrile illness, AFI). The common causes of AUFI include malaria, dengue fever, enteric fever, leptospirosis, rickettsiosis, hantavirus and Japanese encephalitis [2]. 

The Objective of our study was to determine the clinical parameters of the study participants admitted in the Internal Medicine ward at Indira Gandhi Medical College, who were suffering from any kind of Acute Undifferentiated Febrile Illness.

It was a hospital-based cross-sectional observational study that was conducted in the Department of Internal Medicine at Indira Gandhi Medical College, Shimla, Himachal Pradesh, India. The study was conducted over a period of one year. All patients who were admitted with the Acute Undifferentiated Fever defined as temperature ≥ 100°F and history of febrile illness of 2–14 days duration, with no localized cause were included in the study. The data was collected, cleaned and entered into Microsoft Excel spreadsheet and transferred to Epi info version 7.2.1.0 software. The categorical variables were expressed in terms of frequencies, proportions, and percentages with 95% confidence intervals. The continuous variables were expressed as means ± standard deviation. 

We conducted this cross-sectional study on 156 study participants who were admitted in the department of general medicine at Indira Gandhi medical college Shimla. In our study we found that there were 58% of males and 42% females. The study participants in our study belonged to rural area mostly whereas only 22% of them were from urban areas. The mean age group of the study participants was 37. 37 years with a standard deviation of 14.2 years. The age group of the study participants in our study ranged from 19 years to the maximum of 70 years. The mean duration of stay in the hospital was 5.30 days with a standard deviation of 3.2 days. The duration of stay ranged from a minimum of two days to a maximum of 15 days. The study participants admitted for acute undifferentiated febrile illness had fever with mean duration of 8.38 days and a standard deviation of 3.7 days before hospitalization. The range of the duration of fever before hospitalization was between 1 and 21 days in our study participants. (Table 1)

Table 2 shows the description of variables according to associated comorbidities among our study participants. We found that the most common associated comorbidity among the patients admitted for acute undifferentiated febrile illness was hypertension followed by diabetes. The next most common comorbidity that was associated in our study participants was cardiovascular diseases which was found to be present in in approximately 14% individuals. Whereas is 5.1 % of our study participants was suffering from chronic kidney disease, only 2.6% of  the study participants were found to have been suffering from chronic obstructive pulmonary disease. However, 67. 9% of the study participants was not suffering from any associated comorbidities at the time when they were admitted in the department of general medicine for acute undifferentiated febrile illness.

The table 3 gives a description of variables according to vitals at the time of admission. We found that the mean respiratory rate of our study participants was found to be 21.7 per minute with a standard deviation of 3.1 per minute. We found that nearly 40% of the individuals had presented with respiratory rate of more than 22 per minute among our study participants at the time of admission in the department of general medicine. The mean systolic blood pressure of our study participants was found to be 1 14.7 mm of Hg with the standard deviation of 11.4 mm Hg. The mean diastolic blood pressure of the study participants was found to be e 73.1 mm Hg with the standard deviation of 6.6 mm Hg. The mean heart rate of the study participants in our study was found to be 93.2 beats per minute at the time of admission with a standard deviation of 13.0 beats per minute. On pulse oximetry it was found that the saturation of oxygen was nearly 92 percent with standard deviation of 4.1 %. Nearly 44% of the individuals had presented with systolic blood pressure of less than hundred mm Hg and 62% of the individuals were found to have a heart rate of more than 90 beats per minute. The oxygen saturation as found on pulse oximetry was found to be less than 90 among 64% individuals in our study.

Table 1: The range of the duration of fever before hospitalization

Table 2: Description of variables according to associated comorbidity (N=156)

Table 3: Description of variables according to vitals at the time of admission (N = 156)

In our study we found that majority of the patients who were admitted to the department of general medicine at Indira Gandhi medical college Shimla for males as compared to females. Study conducted by Rellar et al. [3] found that most of the study participants were males which is in concordance with study. The study conducted by Raina et al. [4] also showed more males were suffering AUFI as compared to females which is also in line with study. However, the study conducted by Shelke YP [5] found that there were more females as compared to the males which is not in concordance with our study.

In our study we observed that the majority of the study participants belonged to the rural areas of Himachal Pradesh. This is possibly due to the fact that nearly 80% of the of the population resides in the rural and backward areas of Himachal Pradesh where most common occupation of the people is agriculture. The rest of the people of Himachal Pradesh who pursue for better career opportunities and higher studies reside in the urban areas. This study finding is in concordance with the study conducted by Andrews et al. [6] where a multicentric study done in South in India showed that the majority of the study participants belonged to the rural areas. Study conducted by Murdoch et al. [7] also showed similar findings in their study conducted in Nepal. However, the study conducted by Kunti et al [8] show that most of the study participants worked in the urban areas of Karnataka. Kingston et al also found that the majority of the study participants belonged to the urban areas. These two studies are not in accordance with our study [9].

The mean age of the study participants in a study was found to be nearly 38 years ranging from 19 to 70 years. This is possibly due to the fact that the majority of the population of this age group is working in the fields where they may contract the diseases such as dengue, malaria and scrub typhus. The study conducted by Kumar et al. [10] found that the study participants had a mean age of around 26 years which is not in line with our study. Zaki et al. [11] also showed that the mean age of the study participants was around 30 years which is also not in terms with study. Chheng et al. [12] found that the mean age of the study participants in their study at the time of hospitalization was over 50 years which is also not in line with the study. The study conducted by Punjabi et al. [13] found that the mean age of the study participants was 40 years which is in accordance with our study. Ahmad et al. [14] also found that they study participants had a mean age of 39 years which is also in similar lines with our study.

The mean duration of stay in the hospital in our study was around 5 days whereas the mean duration of fever before hospitalization was found to be around 9 days in our study. This longer duration of fever before the hospitalization could be due to the fact that most of the population of the hilly state of Himachal Pradesh do not have access to the public transportation facilities during the night hours. In winters it becomes very difficult for the people to reach the medical college from the far flung areas as the hills are covered with snow most of the times. This study is not in accordance with the study conducted by Andrews et al. [10] as well as the study conducted by Arora et al. [15] and Das et al. [16].  However, Ellis et al. [17] found that the duration of stay in the hospital was around 6 days which is in similar lines with our studying. McGready [18] and Mittal et al. [19] found at the duration of fever before hospitalization was around 10 days which are also in similar lines with study.

In our study we found that the vitals of the study participants were mostly stable. This was probably due to the fact that most of them were stabilized either in the the ambulances or in the first referral units. This is in similar lines with the study conducted by Rani RV et al and Sabchareon A et al. [20].

Nearly 80% of the study participants resided in the rural areas of Himachal Pradesh. The mean age of the study participants in our study was found to be 38 years. The mean duration of stay in the hospital was 5.30 days and the mean duration of fever before hospitalization was 8.38 days. The most common comorbidity among the patients admitted for AUFI was Hypertension(32.1%) followed by Diabetes Mellitus (24.3%).

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