Comparison between Watermelon Frost and Ribavirin Aerosol in the Treatment of Oral Herpes in Hand, Foot and Mouth Disease

369 mild HFMD patients were randomly assigned to being treated with
either ribavirin or watermelon frost. The course of treatment was 5 days. After this
period, the effect of the treatment was evaluated, including the time of disappearance
of oral ulcers, fever clearance and vesicles in the hand or foot, together with the clinical
grading of the symptoms.

incidence of HFMD is 1.2 per 1,000 persons per year in China and the disease is responsible for 350-900 reported deaths annually [4]. HFMD is usually self-limiting with most sufferers manifesting a mild form of the disease, with relief of symptoms seen within 7-10 days [5].
However, a few cases can progress into a severe condition with complications, including encephalitis, neurogenic pulmonary edema, pulmonary hemorrhage and circulatory failure. These complications are life threatening if treatment is not given promptly [6]. Oral herpes is one of common symptoms of mild HFMD. This normally causes pain of oral ulcers which interfere with the diet and can even lead to dehydration and liquid imbalance. Currently, there are no specific treatments for HFMD. The most common treatment is only to relieve the offending symptoms by supportive therapy and the use of antiviral agents and immune-potentiators.
In this study, we conducted a clinical trial to study the efficacy and safety of both ribavirin aerosol and watermelon frost in treating oral herpes brought about by mild HFMD cases.

Inclusion Criteria
All patients were younger than 6 years old and were clinically diagnosed with HFMD according to the 'Guidelines for HFMD Diagnosis and Treatment' issued by the Ministry of Health of China (version 2010), published by the National Health and Family Planning Commission. Up to 72 hours of the initial diagnosis, patients were not subjected to any antiviral agents or analgesicantipyretics. The clinical symptoms ruled out any other diseases.

Exclusion Criteria
Severe HFMD cases were excluded from the study as well as cases which appeared to be developing into severe HFMD cases during the period of the study. Patients who had taken antivirals (including Chinese patent medicines) 7 days before diagnosed.
Cases complicated with bacterial infections (C-reactive protein > 8 mg/L) and participants who were allergic to ribavirin or watermelon as well as patients who had participated in other clinical studies within the last 30 days were also excluded.

Randomization
All participants were randomly grouped into watermelon or ribavirin groups. There were 187 cases in the treatment group, who received watermelon frost and the ribavirin groupwith182 cases received ribavirin aerosol. According to the group, participants were registered and provided with the drugs which were used immediately.

Methods
Both groups followed the "Diagnosis and treatment guidelines of HFMD (2010 edition)" in order to follow the supportive therapy. The ribavirin group used ribavirin aerosol (Shanghai Sine Pharmaceutical Company Limited). This drug should first be taken 4 times in the first hour, followed by once every other hour; after 2 days, it should be taken 4 times every day. Each time it is taken, the dose applied should be that the aerosol be pressed 2-3 times.

Evaluating Indexes
We followed up the patients in the two groups every day in the treatment period. The concrescence time of oral ulcer before and after the treatment was recorded and the clinical symptoms were scored. With both groups of patients, the disappearance time of fever and roseola from the hands and feet were observed and recorded, and the clinical curative effect as well as the comprehensive curative effect were evaluated.

Curative Effect Standards
Oral Herpes: 1) Recovery: oral herpes disappeared, receiving the correct diet and no obvious drooling noted; 2) Excellent: the amount of herpes reduced to more than half of the primary and an obvious improvement in the diet; 3) Effective: the amount of herpes receded to approximately 1/3-1/2 of the initial amount seen and a slight improvement of the diet; 4) Invalid: the amount of herpes seen was the same or was increased compared to the initial amount seen and the diet was not better.

The clinical symptoms, including hand and foot rash and coughing:
1) Recovery: the clinical symptoms score was zero; 2) Excellent: the score was reduced ≥ 2; 3) Effective: the score was reduced ≥1 and <2; 4) Invalid: the score had not changed or was increased (the curative effect evaluation of each single clinical symptom was directed only to the single clinical symptom deviant).

Safety Assessment
The safety assessment index included any adverse events, laboratory examination and any changes of lifestyle during seen from the pre-therapy to the post-treatment period observed during the clinical treatment.

Statistical Analysis
All statistical procedures were performed with SPSS16.0 software. The enumeration data were expressed as percentages and the measurement data were expressed as the means ± SD (χ ± s). All reported P values were two-sided, and all P values were statistically significant if P<0.05. The category variables were compared by the chi-squared test and the continuous variables of two groups were compared by group t-test.

Results
380 cases met the inclusion criteria. Of the380 participants, 4 participants were excluded because they were treated with antiviral medicines within 7 days before the administration. 2 were excluded because they were allergic to ribavirin or watermelon frost. 5 were excluded because their CRP＞8 mg/L. 369 cases were enrolled in our study. 178 cases from the watermelon frost group completed the trial. 5 cases were excluded because they developed into severe HFMD and another 4 cases were lost during the trial. 175 cases from the ribavirin group completed the trial in which5 cases were lost and two cases developed for severe HFMD (Fig. 1). There was no statistically significant difference between of lost patients in the two groups. The baseline demographic characteristics, clinical features, and laboratory variables were similar between the two groups of patients (Table 1).

Curative Effect of Oral Herpes
After 5 days of administration, the effect on the oral ulcers of the watermelon frost group was superior to the ribavirin group (χ2=4.338, P=0.037; Table 2).

Fever Clearance
After 5 days, the grade of fever was 0.05±0.29 both in the watermelon and in the ribavirin groups and there was no statistical difference between the groups (z=0.18, P=0.8589). The temperature of patients in the watermelon frost group dropped to lower than the ribavirin group (χ2=6.776, P=0.009; Table 2).

Clinical Outcomes
5 days after the initial treatment, the difference of the development of skin rash was not statistically significant (χ2=0.081, P=0.776; Table 2).The score for coughing was 0.07±0.25 in the watermelon frost group and 0.17±0.42 in the ribavirin group before using the drugs. After 5 days of treatment, the scores in both the watermelon and ribavirin groups were 0.03±0.18 and therefore there was no statistical difference between the two groups (χ2=3.202, P=0.074; Table 2). The scores for fever were 0.93±0.96 and 1.03±1.04 in the treatment and ribavirin groups, respectively, before using the drugs. After 5 days, the scores were reduced to 0.05±0.29 both groups (z=0.18, P=0.8589) (Table 2 & Figure 1). Note: Oral herpes score: 0: no herpes in isthmus of fauces; 1: Herpes distributed within 1/2 isthmus of fauces; 2: Herpes distributed more than 1/2 isthmus of fauces; 3: Herpes distributed overlapping the isthmus of fauces.
Cough: 1: some coughing, no dysphoria 2: Cough frequently, no impact on the sleep quality, sometimes progressed be dysphoria, but easily to comfort; 3: Severe coughing, waking at night because of coughs, easily progress to dysphoria, difficult to comfort.
Skin rash: 1: Rash distributed in one place of the skin; 2: Rash distributed in two places of the skin; 3: Rash distributed in more than three places of the skin.

Safety
During the period of treatment, the vital signs of the two groups were without any obvious difference and were not statistically different between the two groups. There was no statistical difference between the levels of white blood cells, platelets and hemoglobin in the two groups after the treatment. The white blood cells count of 2 patients in the ribavirin group decreased to 3.5×109 ／L and 4.2×109／L in the two groups, respectively. There was no serious adverse event observed in the two groups. One case was considered to be meningitis with increasing temperature, heart rate, and breathing. These symptoms were deemed not to be related to the drugs used in this study.

Discussion
HFMD is a highly infectious disease that is spread mainly by  [10,11]. Several recent clinical studies had proven that both ribavirin and watermelon frost have efficacy dealing with HFMD [12,13]. However, these studies had some limitations, such as these trials were restricted to a small sample and therefore cannot reflect the general population. Also, there is no trial, as yet, to compare the efficacy and safety between the two drugs in HFMD treatment.
In this study, we conducted a clinical randomized controlled trial between the use of ribavirin and watermelon frost in the treatment of HFMD.
The total efficacy rate of the watermelon frost group is higher than the ribavirin group. Monitoring the vital signs and whole blood routine parameters during the treatment period, there was no statistical difference between the two groups of white blood cells, platelets and hemoglobin before and after treatment. There was no adverse reaction such as dizziness or vomiting in either group. Our study illustrated that ribavirin aerosol and watermelon frost are both effective for treating mild HFMD oral herpes. But there was no statistical difference between the two groups for the curative effect on coughing and fever associated with the disease.
There was no adverse reaction in either of the two groups and both drugs performed with respect to safety. In summary, mild HFMD is a viral infection and so watermelon frost could replace ribavirin aerosol to treat oral herpes. Watermelon frost is convenient, shows no adverse reaction and avoids the side-effects associated with ribavirin. Children tend to have a good compliance with watermelon frost, and it can relieve their pain as well as the burden on medical staff. Watermelon frost has the potential of being of a good product for future use in pediatric medicine.

Acknowledgement
We are grateful to all the members which participate in this study.

Funding
The project was supported by a Self-finance Guangxi Medical Fund to J.Z. (No. Z2013047).

Availability of Data and Materials
The data supporting the findings detailed in this paper are presented in the 2 tables and 1 figure within the main paper and are available for inspection from Drs Jingzhi Zhong (842412593@ qq.com) and Suren Sooranna (s.sooranna@imperial.ac.uk).

Authors' Contributions
All the authors except YH and SRS were involved in the acquisition and analysis of the data. JZ, YH and SRS were involved with the interpretation of the data and helped to draft the manuscript. JZ and YH conceived of the study and participated in its design and coordination. All authors were involved in drafting/ revising and approving the manuscript.

Patient Consent for Publication
All participants provided written informed consent for their willingness to participate in this study.