Rational approach to Treat Cases of LSD in Cattle
Dr Abdul Samad, M.V.Sc., Ph.D. (Canada) Former Dean and Director of Instruction, MAFSU
NB:Please note these recommendations are based on the published literature and my own clinical experience. The veterinarians are requested to make their own choice based on the condition of the presented cases. For helping the farmers and the veterinarians, I will be happy to offer free tele-veterinary consultations. You may share the case details and video / images on my WhatsApp number 9969371999 or email- drasamad11@gmail.com
I am happy that the blog received your attention in the right spirit and many veterinary friends sent emails and messages. Few veterinarians gave an account of diversity of symptoms recorded and have been asking me how to treat these syndromes. In this blog I am sharing my protocol, which I have followed successfully with good results even in complicated and recumbent cases. For purpose of clinical intervention, I have divided LSD into two stages:
Stage I:
High fever, skin lesions, clotting defect, respiratory lesions, mild thrombocytopenia, enlarged lymph nodes:
In this stage the treatment goal should be to support the animal body get rid of virus by supporting inflammatory response to remain consistent, (b) administer specific antivirals to reduce virus concentration (not total elimination) and (c) put a stop to spread of virus from skin lesions. In fact, most of the symptoms in this stage are indicative of host body immune response to eliminate virus through cellular reaction mode. Support the animal by not administering anti-inflammatory drugs.
Take care of fever:
Fever is an indicator of inflammation and immune response. The animal body is creating a hostile environment for the virus to put a stop to its multiplication. Do not bother to bring down fever unless it exceeds 106 oC. I do not fever even plain antipyretic at this stage Please do take out time to read this review, it will clear many doubts on when antipyretics should be used1. I prefer cold sponging / cold bath to bring down fever. If animal appears to be in great pain and discomfort, give Injection Paracetamol, @ 10-15 mg per kg body weight slow intravenous (take at least 10-15 minutes) followed by oral route (10 mg per kg). I will avoid intramuscular injection to spare the animal from pain of injection. Paracetamol is absorbed in ruminants and will appear in blood within 2-3 hours of administration. The goal should be to discontinue paracetamol once fever is below 105.
Bring down viraemia to threshold level:
DNA viruses are difficult to get rid of totally with antiviral drugs, so the goal here is to reduce virus load for the animal body to tackle the virus cellularly. I found Acyclovir to be effective (based on relief in symptoms and not virus load count). If virus load is reduced the immune response also tapers and there is improvement in symptoms. I must admit that there is no published report on efficacy of acyclovir in LSD, but I have recommended its use in quite a few animals, and the feedback is encouraging. Another advantage is that this drug will also take care
of latent herpes virus infection, which, in my opinion, is a major cause of severity in the present outbreak. I will review this topic in my next blog as there is now evidence of synergism between the two viruses. Acyclovir injection 1.0 to 1.5 g intravenous can be administered to start with. The drug has shorter half-life, hence the follow up dose could be oral (3.2 to 4.0 g) for at least 3-5 days. Once fever subsides to 104, this may be discontinued. Tablets are available in 400 and 800 mg strength. Take care of pulmonary oedema: The respiratory signs are due to pulmonary oedema, do not neglect this as, if not taken care of, it will lead to right ventricular compromise. My preference is injection Lasix 20 ml (1.0 g) iv. No need to dilute, give slow intravenous injection. Furosemide oral is also absorbed. Do not overdose, for fear that it would cause hypokalaemia. Deriphyllin / aminophylline, class of bronchodilators are not effective, moreover, this drug in ruminants has short half-life. Antibiotic: You must settle for an antibiotic that is sufficiently partitioned in skin, lung and other soft tissues. In general, fluroquinolones are a better choice, and I prefer levofloxacin injection. In order for sustained release, I prefer giving this subcutaneous. As a follow up my choice is Trimethoprim + sulpha bolus, twice day oral for five days. Do not overuse antibiotics.
Topical viricide application to prevent spread of virus:
This is an important aspect of control. Since the skin lesions are rich in virus load, transmission from the crusts must be avoided by application of viricides on the skin lesions.
There are three options:
Application of glacial acetic acid- It is a weak acid available in the market. Soak in cotton cloth/ or cheese cloth and apply all over the lesion area. While using, the veterinarian should be aware that its fumes when inhaled are toxic and may cause problems, such as, giddiness, headache. The fumes may also cause eye irritation, hence open the bottle away from face.
Ascorbic acid 1%:
This is also an effective viricide
- A limitation of this drug is that aqueous solution is not stable, beyond 24 hours, hence every time fresh solution needs to be prepared. A practical way would be to carry 10 g sachets of ascorbic acid to be dissolved in one L clean water. It can be applied with towel or cotton cloth. Ascorbic acid is available even on Amazon. You can teach this to the farmer so that he carried out this every day. Ascorbic acid in pure form is also available on Amazon. Local antiviral ointment: This must be used in open LSD wound and ulcers, as else these lesions will continue to shed virus. There are also reports that virus in skin lesions remain for a long time. I found Acyclovir ointment 5% to be very effective. Taking care of open wound: Open wounds and ulcers are major menace and must be taken care. A barrier-technology based antiseptic spray kit is undergoing trials. Feedback is very good as the film formed after spray keep the wound moist, insulated from external contamination and even if flies lay larvae, these would penetrate. Even extensive open wounds would heal in 5-7 days. I would be happy to supply free of any cost the chemical bandage kit to few veterinarians. The spray can also be used after application of acyclovir ointment. It will cover the antiviral drug allowing slow release
- . Energy supplements: In LSD the entire gastrointestinal tract is affected with lesions, hence providing an energy supplement that provides glucose would be helpful, in case the animal’s dry matter is seriously reduced. Rumen-bypass starch is my choice, as enzymatic digestion of starch in the intestine results in storing of glucose in the intestinal cells sparing the overall glucose pool. Feeding of
RP-starch results in early healing of intestinal lesions, as evidenced by resumption of feeding. It is an interesting product concept about which I will share details in my next blog. Stage II-
Generalized Oedema and Cardiac Function Compromise Brisket oedema, malaise, cardiac compromise, recumbency are the signs suggestive of severe pulmonary oedema leading to right heart compromise. In such cases the treatment goal should be: (a) to improve cardiac output, (b) reduce pulmonary arterial pressure and (c) reduce fluid load. I have found following protocol to be effective in saving at least 70-75% cases. Digoxin / Lanoxin: It is a cardiac glycoside indicated to improve ventricular function. In these cases, since oedema is of pulmo-cardiac origin, digoxin is life-saving. It is available as 0.5 mg in 2 ml ampules. The dose I use is, 10 ml (2.5 mg) to be given slow intravenous. This drug must be administered only by a qualified veterinarian as monitoring of heart rate is critical. In cases where I have tried this drug, there is remarkable improvement in respiratory function and reduction of brisket oedema. The overall condition also improves. Oral digoxin is not absorbed in ruminants, hence only parental injection should be given.
Diuretic:
My preference is loop diuretic, such as, furosemide. My preferred dose is 500 mg given intravenous every alternate day. Do not overuse this drug as one of its side effects is hypokalaemia, which may further compromise cardiac function. In addition, the measures described for stage I -LSD described above, especially, energy supplement, skin lesion nursing with barrier film spray, should be continued, depending on the animal’s clinical presentation.
Concurrent infections:
Few veterinarians have asked me how to deal with theilaria and anaplasma infections in LSD. The recrudesce of protozoan parasite is due to immunosuppression (specially cellmediated immune response). I would not bother about these infections right now. I recommend checking Hb levels three days apart, and if the finding is consistent fall in PCV and blood profile suggestive of haemolytic syndrome, then only I will burden the animal body with noxious antiprotozoal drugs.
Please Remember:
Although there are no reports on human transmission in India, as yet, but cases have been reported from other countries. Human exposure is associated with concurrent herpes infection. The veterinarians are requested to use mask and gloves while attending these cases. Similar instruction should also be given to the farmers. Please do share your feedback on drasamad11@gmail.com or ‘WhatsApp’- 9969371999. I know, many veterinarians are experimenting with alternate approaches. Please keep record of your work, photos, if any. This will enable us to develop a robust protocol to be followed.
Reference:
2 Kamal, S. A., Med Clin Arch, 2019 doi: 10.15761/MCA.1000161
3 Conflict of interest declaration- I am one of the inventors of the barrier film technology, and a patent has been filed in India and PCT.
1 Karen I. Plaisance, Philip A. Mackowiak,
Antipyretic Therapy-Physiologic Rationale, Diagnostic Implications, and Clinical Consequences- Arch Intern Med. 2000;160(4):449-456. doi:10.1001/archinte.160.4.449
